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1	CHEMISTRY AND MATERIAL SCIENCES	ABS-258
SYNTHESIS AND CHARACTERIZATION OF HYBRID COMPOUNDS \(R_2SnI_4\), R = \(PMA^+\) \((C_7H_7NH_3)\) AND \(PEA^+\) \((C_8H_9NH_3)\) Nelly Safitri Anwari, Djulia Onggo and Muhamad A. Martoprawiro Inorganic and Physical Chemistry Division, Faculty of Mathematics and Natural Sciences, Institute of Technology Bandung-ITB, Jl. Ganesha 10 Bandung, Indonesia Abstract Hybrid compounds \(R_2SnI_4\) are composed of cationic organic compound ammonium \(R^+\) embedded in anion layer of \(SnI_4^{2-}\) complex. This compound has superior photoluminescence properties so that can be used as an active ingredient in solar cells, photodetectors, and LED. In this study we prepared the hybrid compound using one-pot reaction by mixing all reactants SnO, HI, \(H_3PO_2\), and amines (PMA, PEA) and heated at 90-100 \(^0C\). The hybrid products were isolated as black and deep red crystals with the respective chemical formulas are \((PMA)_2SnI_4.HI\) and \((PEA)_2SnI_4.2HI\) with \(PMA^+\) = \(C_7H_7NH_3\) and \(PEA^+\) = \(C_8H_9NH_3\). The molecular formulas have been determined using the elemental analyser, atomic absorption spectroscopy and argentometric titrations. The thermal stability of \((PEA)_2SnI_4.2HI\) is 178 \(^0C\) and higher than \((PMA)_2SnI_4.HI\) that start to decompose at 129 \(^0C\). Keywords: Hybrid, \((PMA)_2SnI_4.HI\), \((PEA)_2SnI_4.2HI\), photoluminescence Share Link | Plain Format | Corresponding Author (nelly safitri anwari)

2	CHEMISTRY AND MATERIAL SCIENCES	ABS-5
The Technique to Modify Imprinted Polymer onto Nanofiber Siti Oryza Sativa, Muhammad Ali Zulfikar, Muhammad Nasir, Nurrahmi Handayani Institut Teknologi Bandung Abstract Ion-imprinting technology (IIT) has been used to prepare the ion-imprinted polymers (IIPs) for the sorption of metal ions with high selectivity. To design selective and specific recognition sites, ion imprinting used alteration methods to detect targets by mimicking natural recognition ions. In this research, we synthesized the imprinting polymer nanofiber. Nanofiber (NF) has been synthesized using polyacrylonitrile (PAN) polymer dissolved in dimethylformamide (DMF) with electrospinning method. In order to study the technique to immobilize imprinting polymer onto nanofiber, we tried it with non-imprinted polymer (NIP) with coating method. Here, we studied the efficiency of this method. To synthesize the NIP, we used ethylene glycol dimethacrylate (EGDMA), benzoyl peroxide (BPO) and acetonitrile as crosslinking agent, free radical initiator and porogen, respectively. Scanning Electron Microscope (SEM) and cross-section have been used to study the morphology of synthesized NIP-NF. From this work, we studied the technique to synthesize NF and to modify it with imprinting polymer technology. Keywords: imprinting polymer technology, nanofiber, polyacrylonitrile, coating Share Link | Plain Format | Corresponding Author (Siti Oryza Sativa)

3	CHEMISTRY AND MATERIAL SCIENCES	ABS-264
Inorganic Solid Catalyst Derived From Fishbone Waste (Katsuwonus Pelamis) For Transesterification Of Palm Oil To Biodiesel Siti Maisarah (a), Surya Lubis (b), Rara Mitaphona (c), Desi Novita (b), and Muliadi Ramli1 (b*) a) Graduate Program of Chemistry, Universitas Syiah Kuala, Faculty of Mathematics and Natural Sciences, 23111 Banda Aceh, Aceh, Indonesia, *Corresponding author, email: muliadiramli[at]unsyiah.ac.id b)Department of Chemistry, Universitas Syiah Kuala, Faculty of Mathematics and Natural Sciences, 23111 Banda Aceh, Aceh, Indonesia 3)Doctoral Program of Mathematics and Applied Sciences, Universitas Syiah Kuala, 23111 Banda Aceh, Indonesia Abstract This research has utilized fishbone waste of tuna (Katsuwonus pelamis) which has been collected at the Lampulo fish market in Banda Aceh. Inorganic oxides have been derived from fish bone waste through the decomposition method at high temperature, namely the calcination process in an air atmosphere at 900&#7484-C for 4 hours. The physicochemical properties of obtained inorganic oxides were characterized using XRD and SEM-EDS. The characterization results indicated the composition of the calcined fishbone contained hydroxyapatite, CaCO3, CaO in which the hydroxyapatite phase has been major component. Furthermore, the calcination process has a positive impact for improving the physical morphology and crystalline phase of inorganic oxides. Finally, obtained inorganic catalyst based on fishbone waste has applied for transesterification of palm oil with methanol, whereas resulting in three main compounds, consisting of trimethyl borate, methyl laurate, and methyl octanoate. Keywords: fishbone, Katsuwonus pelamis, heterogeneous catalyst, transesterification, palm oil Share Link | Plain Format | Corresponding Author (Muliadi Ramli)

4	CHEMISTRY AND MATERIAL SCIENCES	ABS-11
Separation Performance of Poly(vinylidene fluoride)-Cellulose Acetate Blend Membranes for Reactive Orange 16 Dye Removal Muhammad Reza (a*), Cynthia Linaya Radiman (b), Adean Mayasri (a), Ratu Fazlia Inda Rahmayani (c) a) Department of Chemistry Education, Faculty of Teacher Training and Education, Universitas Islam Negeri Ar-Raniry, Jl. Syeikh Abdur Rauf, Banda Aceh 23111, Indonesia *muhammad.reza[at]ar-raniry.ac.id b) Inorganic and Physical Chemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Bandung, Indonesia c) Chemistry Department, FKIP, Universitas Syiah Kuala, Jl. Tgk. Hasan Krueng Kalee, Banda Aceh 23111, Indonesia Abstract Reactive orange 16 (RO 16) is water soluble synthetic dye under azo reactive dyes that causes environmental pollution due to its harmful and mutagenic properties. Polymer-based membrane is one of technologies which commonly used to separate RO 16 from aqueous solution that frequently came from textile waste. The membranes were prepared via phase inversion method using various concentrations of cellulose acetate (CA) from 1 and 5 wt.% that blended into poly(vinylidene fluoride) (PVDF). The separation performance of membranes toward RO 16 was evaluated using flux measurement and fouling resistance. Compared to pristine PVDF membrane, PVDF-CA membranes have higher water flux where the values reached 125.62 L m-2 h-1 for blend membrane with 5% CA. This composition also exhibits the lowest fouling, indicated by the highest flux recovery ratio of 88,5%, where the water flux recovered to 111.26 L m-2 h-1 after backwash. In addition, this performance was supported by the highest reversible fouling. The morphological properties were also analyzed using Scanning Electron Microscope - Energy Dispersive X-Ray (SEM-EDX). The composition of oxygen atoms increased from 4.70 to 10.47 wt.% along with CA addition. All compositions show good separation performance, indicated by high percentages of rejection that greater than 90% for RO 16 removal. Keywords: reactive orange 16- poly(vinylidene fluoride)- cellulose acetate- membrane technology- fouling resistance Share Link | Plain Format | Corresponding Author (Muhammad Reza)

5	CHEMISTRY AND MATERIAL SCIENCES	ABS-275
A Simple Analytical Method to Determine the Fraction of {001} Anatase Crystals Facet Fry Voni Steky (a,b), Didi Prasetyo Benu (a,b,c), Rino Rakhmata Mukti (b,d), Brian Yuliarto (d,e), Veinardi Suendo (b,d*) a) Doctoral Program of Chemistry, Faculty of Mathematics and Natural Sciences, Department of Chemistry, Institut Teknologi Bandung, Bandung 40132, Indonesia b) Division of Inorganic and Physical Chemistry, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha No. 10, Bandung 40132 Indonesia *vsuendo[at]chem.itb.ac.id c) Department of Chemistry, Universitas Timor, Jl. Eltari, Kefamenanu 85613, Indonesia d) Research Center for Nanosciences and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha No 10, Bandung 40132, Indonesia e) Engineering Physics Department, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha No. 10, Bandung 40132 Indonesia Abstract There are several methods to quantify the most reactive facet {001} in anatase. However, most methods involve a series of expensive and complex experimental techniques. This work demonstrated a simple method to quantify the {001} facet of anatase crystals based on a comprehensive XRD analysis. We have calculated the fraction of {001} facet using a geometric model of a truncated square-bipyramidal-shaped crystal based on the crystal habit of anatase. The presence of truncated square-bipyramidal-shaped crystallites in the anatase phase was confirmed by HRTEM. The peaks in the XRD pattern at 37.7 and 48.0 degrees represent the (004) and (200) diffraction planes, which are coherent with the (001) and (100) diffraction planes of the unit cells, respectively. Applying the Scherrer Equation, these peaks full width at half maximum (FWHM) corresponds to the average thickness and length of the anatase crystallites. Keywords: anatase phase, crystal habit, crystal facet, facet-fraction determination, truncated square-bipyramidal-shaped crystal Share Link | Plain Format | Corresponding Author (Fry Voni Steky)

6	CHEMISTRY AND MATERIAL SCIENCES	ABS-276
Phytochemical Screening and Antioxidant Potency Test of Lindur Fruit Peel Extract (Bruguiera gymnorrhiza) Ana Mardliyah(a*), Naily Rizqiyah(b) Universitas Islam Negeri Walisongo Semarang Abstract Degenerative diseases caused by free radicals can be treated with antioxidants, and the lindur plant (Bruguiera gymnorrhiza) is one of the mangroves that has the potential as an antioxidant. This research aims to determine the IC50 value of the antioxidant activity of lindur fruit peel extract and to analyze its secondary metabolite content. Extraction process of lindur fruit skin by maceration method. The yield from the maceration process of the crude methanol extract was 78.55% while that of the fractionation process from n-hexane, ethyl acetate and methanol-water were 1.2%, 1.52% and 65.24%, respectively. Secondary metabolites were analyzed by the phytochemical screening method. Based on the phytochemical test, the methanol crude extract contained alkaloids and saponins while the n-hexane fraction contained steroids, the ethyl acetate fraction contained alkaloids, and the methanol-water fraction contained saponins. Antioxidant activity was determined using the DPPH (1,1-diphenyl-2-picryhidrazil) method. The test results showed that for crude methanol extract the IC50 was 48.931 ppm and for the most active fraction was the ethyl acetate fraction the IC50 value was 73.040 ppm followed by the n-hexane fraction IC50 76.460 ppm, and the methanol-water fraction IC50 94.291 ppm. Keywords: Bruguira gymnorrhiza, lindur, antioxidant, dpph, secondary metabolites Share Link | Plain Format | Corresponding Author (Ana Mardliyah)

7	CHEMISTRY AND MATERIAL SCIENCES	ABS-281
Preliminary investigation of freeze-thawed hydrogel prepared from commercial Porang flour William Xaveriano Waresindo (a,b), Halida Rahmi Luthfianti (a,b), Dhewa Edikresnha (b,d), Akfiny Hasdi Aimon (b), Tri Suciati (c), and Khairurrijal Khairurrijal (b,d,e *) a) Doctoral Program of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia b) Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia c) Department of Pharmaceutics, School of Pharmacy, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia d) University Center of Excellence - Nutraceutical, Bioscience and Biotechnology Research Center, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia e) Department of Physics, Faculty of Sciences, Institut Teknologi Sumatera, Jl. Terusan Ryacudu, Lampung 35365, Indonesia *Corresponding author: krijal[at]itb.ac.id Full postal address: Bandung (40132), Indonesia Abstract As a tropical country located along the equator, Indonesia has a high biodiversity potential. This diversity allows the birth of various innovations related to the development of natural materials and their utilization in various fields. One of these natural ingredients is Porang tuber from the Amorphophallus muelleri Blume plant. Innovations can be made by engineering natural materials into new forms known as hydrogels which are biocompatible and biodegradable. In this study, hydrogel synthesis was carried out using the freeze-thaw method based on Porang flour which is commercially available in the market. By varying the concentration of Porang flour solution starting from 6, 8, 10, and 12 wt%, the physical properties of the precursor solution and the resulting hydrogel were observed. The concentration of the solution affects the value of the viscosity and density of the porang flour solution with a positive correlation. The increase in concentration also affects the structure and physical appearance of the resulting hydrogel to become stronger, elastic and sturdy. Observation of the morphology of the cross-section of the hydrogel with an optical microscope shows that the pores are connected to each other and get smaller with increasing concentration of the precursor solution. In addition, the degree of swelling study showed a very high-water absorption capacity and at the same time showed a low weight loss. Thus, the hydrogel has been successfully synthesized from commercial Porang flour and based on the results of this initial study, the hydrogel is highly recommended for further development in the biomedical field. Keywords: hydrogel, porang, commercial porang flour, freeze-thaw, physical properties Share Link | Plain Format | Corresponding Author (William Xaveriano Waresindo)

8	CHEMISTRY AND MATERIAL SCIENCES	ABS-26
Determination of Palm Based Hydrotreated Vegetable Oil (HVO) Content in Diesel Sylvia Ayu Bethari (a,b), Handajaya Rusli (a*), Muhammad Bachri Amran (a) a) Analytical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Indonesia b) Testing Center for Oil and Gas ^LEMIGAS^, Ministry of Energy and Mineral Resources Republic of Indonesia *handajaya[at]itb.ac.id Abstract Hydrotreated vegetable oil (HVO) is renewable fuel obtained from the hydrotreatment process of triglycerides palm oil. HVO is potent blending compound because of its similar chemical structure to diesel fuel. The similarity between HVO and diesel fuel on the other hand will make it difficult to test HVO in diesel oil. Determination of the amount of HVO in diesel fuel can be used to ensure that the fuel mixture meets diesel quality specifications. In this research, an analytical method using the GC- FID is developed, and GC-MS is used to conform the structure. Chromatogram of diesel fuel and HVO are significantly different to each other with unique peaks that indicate their main component hydrocarbon. The two peaks with retention time around 17.5 - 17.7 minutes as preliminary identification of the diesel fuel and in the mixture. Peak^s ratio of heptadecane to pentadecane-2,4,6,10-tetramethyl is 1.24 in diesel fuel, whereas heptadecane is found in B0 and HVO also. The mixture of 0-40 %v/v of HVO in diesel blend has excellent linear regression to HVO heptadecane^s peak shown by R2 = 0.9997. The method is applicable to the determination of HVO in diesel mixture with %recovery 96 - 105%. Keywords: diesel fuel- blend- GC-FID- hydrotreated vegetable oil (HVO) Share Link | Plain Format | Corresponding Author (Sylvia Ayu Bethari)

9	CHEMISTRY AND MATERIAL SCIENCES	ABS-33
The stability of silver nanoparticles: Effect of the synthesis and storage time Muhamad Allan Serunting(a,b), Muhammad Ali Zulfikar (a), Henry Setiyanto (a*) a) Analytical Chemistry Research Group, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia *setiyanto[at]itb.ac.id b) Department of Chemical Sciences, Faculty of Sciences, Institut Teknologi Sumatera, Lampung, 35365, Indonesia Abstract Silver nanoparticles (AgNPs) were successfully synthesized with an efficient green route using the kabau pod extract as a reducing and capping agent. The optimum synthesis was at pH 8 near the pH of the aquadest and at a concentration of 1 mM AgNO3. It is also optimal to do it under direct sunlight rather than in the dark or at room temperature. Several characterization instrument parameters were used to confirm the formation of silver nanoparticles. Surface plasmon resonance (SPR) spectra measured using a UV-Vis spectrophotometer peaked at 421 nm, confirming that silver nanoparticles were successfully synthesized. Measurement of the size distribution and zeta potential of nanoparticles using dynamic light scattering (DLS) showed that the resulting silver nanoparticles were mono dispersion is 58.9 nm with a polydispersity index (PdI) of 0.283 and stable for more than 3 months. The zeta potential value is -32.2 mV. The chemical reduction occurs due to the kabau pods extract containing phytochemical compounds (alkaloids, flavonoids, tannins, phenolics, and steroids). In addition, it was also confirmed by the Fourier transformation infrared (FTIR) instrument showing vibrations in the hydroxyl group- carboxyl and amine are involved as reducing and stabilizing agents. AgNPs are also characterized using X-Ray diffraction (XRD). Keywords: Silver Nanoparticles, Green synthesis, Kabau pod extract Share Link | Plain Format | Corresponding Author (Muhamad Allan Serunting Serunting)

10	CHEMISTRY AND MATERIAL SCIENCES	ABS-289
Investigation of 40 kHz Sonication Time and Thermal Effect on The Electrochemical of Ultra Fine Bubbles Arif Adtyas Budiman(a,b,1), Awang Noor Indra Wardana(a,2*), Mulya Juarsa(b,3), Eko Sulistio Hanam(c) a) Master Programme of Physics Engineering, Department of Nuclear Engineering and Physics Engineering, Faculty of Engineering, Universitas Gadjah Mada, Jl. Grafika No. 2, Yogyakarta 55281 1) arif.a.b[at]mail.ugm.ac.id 2) *Corresponding author: awang.wardana[at]ugm.ac.id b) Research and Technology Centre for Nuclear Reactor Safety, Research Organization for Nuclear Energy, National Research and Innovation Agency, Building 80th Science and Technology Research Centre (PUSPIPTEK), South Tangerang, Banten, Indonesia. 3) Mulya.juarsa[at]brin.go.id c) Functional Nano Powder University Center of Excellence (FiNder U-CoE), Universitas Padjadjaran, Jalan Raya Bandung - Sumedang KM 21, West Java, Indonesia Abstract The ultrasonic treatment is used for production and destabilized the ultra fine bubble depend on the exposure time (sonication). The specific characteristic of ultra fine bubble was identified by the zeta potential which correlate to the mean size of bubble diameter. Thus, it is necessary to measure at separate container while analysed in conditional temperature (298,15 K). The hypothetic of dynamic zeta potential may affect the bubbles form, so it could influence the electrochemical properties of liquid. The aim of this study is to confirm the correlation of zeta potential and electrochemical properties through ultrasonic and thermal treatment. The ultra fine bubbles production use an industrial 40kHz ultrasonic transducer (bath-type) with the sonication time and temperature are varied from 1 to 10 minutes and 298,15 to 343,15 K, respectively. The bubble nuclei may obtained in pure water consider the quality is maintained. Meanwhile, a handheld water quality test and particle size with zeta potential analyzer are used for the measurements. The Minitab software is used for statistic analysis. The design of experiments at full factors of dependent variables with the electrical conductivity, total dissolved solids, salinity, pH, and resistivity as the independent variables. It was found that electric conductivity, resistivity, and total dissolved solids are influenced. Furthermore, according to the pareto chart and interaction plot, the important effect of electrical conductivity is thermal changes. In the other case, the electrical conductivity has changed while sonication time are varied at room temperature. By the temperature increased then back to state condition, the zeta potential has no significant changes. Therefore, the electrical conductivity measurement has prospect to be an alternative method for identify the dynamic bubble on thermal process. Keywords: Ultra Fine Bubbles, Sonication Time, Thermal Treatment, Electrical Conductivity, Zeta Potential, Electrochemical, Interaction Plot, Pareto Chart Share Link | Plain Format | Corresponding Author (Arif Adtyas Budiman)

11	CHEMISTRY AND MATERIAL SCIENCES	ABS-291
Adsorption of Ce(III) Metal Ions Using Magnetite-Alginate Composite Crosslinked with Glutaraldehyde Rusnadi, Kendra Laylasafit Analytical Chemistry Research Group, FMIPA, ITB Abstract Cerium (Ce) is one of the rare earth metals with the highest abundance among its group in the form of mineral rocks. It is widely used in the television manufacturing industry, ceramic industry and catalyst. Adsorption is an easy and effective separation method to reduce the amount of Ce(III) ions in wastewater. In this study, Magnetite-Alginate composite crosslinked with Glutaraldehyde (MAG) was developed. The synthesis of adsorbents begins with the manufacture of magnetite in Na-Alginate solution media until magnetite is coated by alginate. The resulting powder is then re-soaked in Na-Alginate solution and glutaraldehyde is added and the reaction temperature is maintained at 80&#8451- so that crosslinking between alginate chains occurs. The successfully synthesized MAG adsorbent was then characterized using Fourier Transform Infrared (FTIR), X-Ray Diffraction (XRD), Scanning Electron Microscopy- Energy Dispersive Spectroscopy (SEM-EDS). Optimum adsorption parameters for Ce(III) uptake using batch method were achieved at pH 4, contact time 4 hours and adsorbent mass 0.05 grams. The Ce(III) ions adsorption followed the Langmuir isotherm model with a maximum adsorption capacity (qm) of 37.73 mg g-1 and a pseudo second-order reaction kinetics model. Keywords: Ce(III), Alginate, Magnetite, Glutaraldehyde, Adsorption Share Link | Plain Format | Corresponding Author (Rusnadi Rusnadi)

12	CHEMISTRY AND MATERIAL SCIENCES	ABS-293
Addition of Nanocrystalline Cellulose into the PVA/Lithium Acetate Solid Polymer Electrolyte Membrane as a Reinforcing Agent Endah Purwanti1, Deana Wahyuningrum2, Achmad Rochliadi1, and I Made Arcana1* 1Inorganic and Physical Chemistry Research Groups, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha No10 Bandung 40132, Indonesia 2Organic Research Groups, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha No10 Bandung 40132, Indonesia Email: 30521011[at]mahasiswa.itb.ac.id *Corresponding author: arcana[at]itb.ac.id Abstract Solid polymer electrolyte materials have been developed as an alternative to liquid electrolytes in lithium-ion batteries. A membrane solid polymer electrolyte acts as a separator and an electrolyte. In this case, it is necessary to develop a new solid polymer electrolyte material so that material that meets the criteria required for a lithium-ion battery. Nanocrystalline cellulose is a natural polymer of nanometer-sized cellulose that has a larger surface area than cellulose and can dissolve in water. Nanocrystalline cellulose can be added to the membrane as a reinforcing agent. In this study, the membrane used was polyvinyl alcohol added with lithium acetate salt at various concentrations. Nanocrystalline cellulose is obtained from the hydrolysis of cellulose synthesized from corn cobs. Hydrolysis of cellulose used 50% H2SO4 aqueous solution at 45 oC with variations in hydrolysis time of 90 minutes (CNC 90^) and 120 minutes (CNC 120^). The resulting nanocrystalline cellulose was characterized by PSA (Particle Size Analyzer), TEM (Transmission Electron Microscope), FT-IR spectroscopy and X-Ray diffraction. Based on PSA measurements, cellulose with CNC 90^ has a particle size distribution with a PI of 0.592 and an average diameter of 274.4 nm with a needle-shaped morphology that can be seen from the results of TEM analysis. In comparison, cellulose with CNC 120^ has a particle size distribution with a smaller PI of 0.510 and a smaller average diameter of 213.8 nm. The x-ray diffraction analysis showed that nanocrystalline cellulose has a crystallinity index of 61%, which is higher than the isolated cellulose. Based on EIS (Electrochemical Impedance Spectroscopy) measurements on the membrane PVA/Lithium acetate/nanocrystalline cellulose, nanocrystalline cellulose can be used as nanocomposites in membrane solid polymer electrolyte for lithium-ion battery separators. Keywords: Solid polymer electrolyte, PVA, nanocrystalline cellulose, Lithium Acetate, lithium-ion battery Share Link | Plain Format | Corresponding Author (Endah Purwanti)

13	CHEMISTRY AND MATERIAL SCIENCES	ABS-294
Obtusinon A and B from the roots of Premna serratifolia Linn. (Lamiaceae) and their cytotoxicity against murine leukemia P-388 cells Ajeng Dalli Alamiah Hadiati, Dikhi Firmansyah, Lia Dewi Juliawaty* Organic Chemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung, 40132, Indonesia. *liadewi[at]itb.ac.id Abstract Premna serratifolia Linn. has been regarded as a beneficial healing herb in tropical Asia and East Africa and is listed as a traditional medicine to treat various diseases in many countries. In Indonesia, P. serratifolia Linn., known as buas-buas, grows a lot in the area of West Kalimantan and is used as traditional medicine and an edible plant. Two icetexane-type diterpenoids, namely obtusinon A and B, were isolated from the root extract of P. serratifolia. These two diterpenoids were isolated for the first time from the roots of P. serratifolia in Indonesia. Their structures were characterized based on 1D NMR spectroscopy data (1H NMR and 13C NMR), 2D NMR (HSQC and HMBC), FTIR, and UV-vis. These compounds were evaluated for cytotoxic activities against murine leukemia P-388 cells. Obtusinon A and B showed noticeable cytotoxic activity, with IC50 values of 0.91 and 0.28 microgram/mL, respectively. These finding indicated that icetexane-type diterpenoids have potency as anti-cancer and that the low-molecular-weight compounds have exceptional cytotoxic properties. Keywords: Premna serratifolia- obtusinon A- obtusinon B- diterpenoids- cytotoxicity Share Link | Plain Format | Corresponding Author (Ajeng Dalli Alamiah Hadiati)

14	CHEMISTRY AND MATERIAL SCIENCES	ABS-296
Microwave-Hydrogen-Plasma-Assisted Synthesis of Black Titania as Photocatalyst in Photodegradation of Rhodamine B Muhamad Nur Siddik(a,b), Ilham(a), Muhammad Fadhil Rizki(a), Didi P. Benu(a,c), Fry V. Steky (a), Kemal L.H. Putra (a), Fairuz G. Nugroho(d,e), Veinardi Suendo(a,e*). (a) Inorganic and Physical Chemistry Research Division, Departement of Chemistry, Institut Teknologi Bandung, Bandung 40132, Indonesia. (b) Science Faculty, Universitas Islam Negeri Sultan Maulana Hasanuddin, Banten 42118, Indonesia. (c) Departement of Chemistry, Universitas Timor, Kefamenanu 85613, Indonesia. (d) Master^s Program in Nanotechnology, Graduate School, Institut Teknologi Bandung, Bandung 40132, Indonesia. (e) Research Center of Nanoscience and Nanotechnology, Institut Teknologi Bandung, Bandung 40132, Indonesia. *)E-mail address: vsuendo[at]chem.itb.ac.id Abstract The application of titania as a photocatalyst under sunlight is well-known to be an inefficient process. TiO2 large band gap makes it less sensitive to light in the visible-NIR region. Black TiO2 receives much attention from researchers due to its narrower band gap and higher sensitivity to light in the visible-NIR region than that of TiO2. Synthesis of black TiO2 using microwave-assisted hydrogen plasma is an effective and efficient method due to its simple and rapid preparation. Our goals are to fabricate a microwave-assisted hydrogen plasma reactor, to study the relation between black TiO2 synthesis time and its physicochemical properties, and to study the photocatalytic activity of prepared black TiO2. The capability of the plasma reactor to generate reactive hydrogen species is measured using OES (optical emission spectroscopy) technique. TiO2 pellets press with 2.5 metric-ton for 5 minutes and then treated in the plasma reactor. Raman Spectroscopy is used to study the chemical structure and polymorphism of the plasma-treated TiO2. Band gap, sensitivity towards UV-Visible region, and relative amount of defects of plasma-treated TiO2 are characterized using UV-Vis DRS. Photoluminescence spectroscopy was carried out to reveal the relative amount of the radiative-recombined defect, a kind of defect related to the photocatalytic activity of plasma-treated TiO2. Microwave-assisted hydrogen plasma reactor was successfully fabricated and able to generate three kinds of hydrogen radiative transitions: H&#945- (21%), H&#946- (8.4%), and H2Fulcher-&#945- (70.6%). Black TiO2 was successfully synthesized with the darkest TiO2 prepared in 3 h of plasma treatment. Hydrogen plasma treatment can create new electronic states, initiate phase transition from anatase to rutile, create defects, narrow the band gap, and enhance sensitivity towards visible light. Here, 1h of plasma treatment provides the leading photocatalytic activity in the photodegradation of rhodamine B at &#955- = 405 nm with k = 3.17x10-3 s-1 and Ea = 11.62 kJ/mol. Keywords: Black TiO2, Microwave-Assited Hydrogen Plasma, Photocatalyst, Photodegradation Kinetics, Reactive Hydrogen Species, Titania Share Link | Plain Format | Corresponding Author (Muhamad Nur Siddik)

15	CHEMISTRY AND MATERIAL SCIENCES	ABS-41
Crystal and Electronic Structure of La-doped SrTiO\(_3\) and Thermoelectric Properties Modelling based on Single Parabolic Band Fainan Failamani (a), Muhammad Sani Kantaprawira (a), Bambang Prijamboedi (a)* a) Inorganic and Physical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology Jalan Ganesha No. 10, Bandung 40132, Indonesia *boedi[at]chem.itb.ac.id Abstract In order to reduce CO\(_2\) emissions, the conversion of waste heat into electricity by thermoelectric devices has gained significant interest. However, the low efficiency of thermoelectric devices limits their applications. Moreover, most thermoelectric materials consist of toxic and expensive elements. The perovskite-structured material SrTiO\(_3\) (STO) has gained a lot of attention due to its unique band structure and consists of cheap and nontoxic elements. Even though undoped STO is an electrical insulator and possess high thermal conductivity, Sr substitution by a higher-valence heavy element could improve its thermoelectric performance. The optimum carrier concentration is crucial in the design of doped STO with high performance. This study aims to determine the effects of Lanthanum doping on the crystal and electronic structure of STO and models its thermoelectric properties using single parabolic band model. La\(_{x}\)Sr\(_{1-1.5x}\)TiO\(_3\) (x = 0, 0.05, 0.1, and 0.15) samples were successfully synthesized using solid-state method. The reduction of the lattice parameter confirmed Lanthanum doping to STO. Diffuse Reflectance Spectroscopy measurements show a slight variation of band gap of La\(_{x}\)Sr\(_{1-1.5x}\)TiO\(_3\) relative to STO. The modelling with single parabolic band model was performed and revealed the carrier concentration for optimum power factor and the electronic contribution to the thermal conductivity. Keywords: Thermoelectric, La-doping, SrTiO\(_3\), single parabolic band model, power factor Share Link | Plain Format | Corresponding Author (Muhammad Sani Kantaprawira)

16	CHEMISTRY AND MATERIAL SCIENCES	ABS-42
Molecular Dynamics Simulation of Interaction between Polyacrylamide-Water for Enchanced Oil Recovery Application Thoriq Vieri Alvianto, Mia Ledyastuti Department of Chemistry, Faculty of Mathematics and Natural Science, Bandung Institute Of Technology Abstract Enhanced oil recovery (EOR) is crude oil extraction method by adding various chemicals into oil well. By this method, 10-20 % more crude oil extracted than without EOR. One of EOR method is chemical injection, which is adding chemical solution into water for increase the effectiveness of waterfloods by increase water viscosity. Polyacrylamide is one of chemical that can be used for EOR method because it can increase water viscosity, but there is few research article about interaction between polyacrylamide and water that makes water viscosity increase. This research purpose is investigate about interaction between polyacrylamide and water by using molecular dynamics simulation. In this research, there are 2 systems to be compared, water only system and polyacrylamide-water system. Other than that, there is variations in number of degree polymerization and water with sodium chloride. With this variations, the systems will compared in terms of viscosity, radius of gyration, solvent accessible surface area, radial force distribution and number of intramolecular hydrogen bonds. The results show that water viscosity, number of intramolecular hydrogen bonds, and solvent accessible surface area increase as number of degree polymerization increases. Radius of gyration and radial force distribution decrease as number of degree polymerization increases. Keywords: Polyacrylamide, Molecular dynamics, Enhcanced oil recovery Share Link | Plain Format | Corresponding Author (Thoriq Vieri Alvianto)

17	CHEMISTRY AND MATERIAL SCIENCES	ABS-298
Hydrazine adsorption conformations on Ni-M (111) (M:Pt, Pd, Ir, Rh) surfaces - A DFT Study Irwansyah (a*), Mohammad Kemal Agusta (b), Muhammad Haris Mahyuddin (b) Laboratory of Computational Material Design, Engineering Physics Research Group, Faculty of Industrial Technology, Bandung Institute of Technology (ITB), Jl. Ganesha 10, Bandung, 40132, Indonesia Abstract Theoretical investigation of the adsorption of Hydrazine (N2H4) on the surface of a Nickel (Ni)-based alloy catalyst (111) is done using Density Functional Theory (DFT). The Ni alloy catalyst is expected to have better catalytic performance than the pure Nickel in hydrazine adsorption due to the influence of alloying elements. Platinum (Pt), Palladium (Pd), Iridium (Ir), and Rhodium (Rh) elements were selected as alloying elements. Hydrazine adsorption in anti, gauche, and cis conformations are studied to obtain stable adsorption configurations. This paper presents the trend of adsorption energy for each Nickel alloy catalyst system (111) for conformations and site variations.The adsorption strength order is NiIr>NiRh>NiPt>NiPd, with cis conformations as the most stable conformation. Keywords: Adsorption, Catalyst, Density Functional Theory, Hydrazine Share Link | Plain Format | Corresponding Author (Irwansyah Irwansyah)

18	CHEMISTRY AND MATERIAL SCIENCES	ABS-303
Effect of Carbonization Temperature of Yellowfin Tuna Fishbone Activated Carbon On Adsorption Performance of Iron (Fe) Zuriah Sitorus (a*), Kurnia Sembiring (a), Emita Sembiring (a), Enda Rasilta Tarigan (a) a) Post Graduate Program (Physics), FMIPA, Universitas Sumatera Utara, Jl. Bioteknologi I Kampus USU, Medan, 20155, Indonesia *zuriah[at]usu.ac.id Abstract Activated carbon extracted from yellowfin tuna fishbone has been successfully fabricated and functioned as an iron (Fe) adsorbent through a direct water filtration scheme. Carbonization temperatures (600, 700 and 800 ^{o}C) were applied in the activated carbon extraction process to determine how much influence it had on the ability to absorb Fe in terms of its pore morphology characteristics. Tests with a Surface Area Analyzer (SAA) were carried out to review the nature of the formed surface pores. Fe absorption performance was analyzed using Atomic Absorption Spectrometry (AAS). The carbonization temperature of yellowfin tuna fishbone has implications for the pore characteristics of the activated carbon produced. The mean pore size, total pore volume and specific surface area of activated carbon with a carbonization temperature of 600 ^{o}C were 5.7456 nm, 0.1896 cc/g, and 74.036 m^{2}/g, respectively. Each of these values decreased, except for the average pore size which increased when the carbonization temperature was increased to 800 ^{o}C. An analysis of what factors might trigger this phenomenon has also been reviewed in detail. In addition, the carbonization temperature also had an effect on the adsorption performance of the Fe formed, where activated carbon with a carbonization temperature of 600 ^{o}C had the most optimum adsorption ability compared to the other two samples. Various factors can be associated in analyzing the effect of yellowfin tuna fishbone carbonization temperature on the adsorbent behavior. Keywords: Carbonizatin temperature- Yellowfin tuna fishbone- Adsorptin performance- Iron (Fe) Share Link | Plain Format | Corresponding Author (Zuriah Sitorus)

19	CHEMISTRY AND MATERIAL SCIENCES	ABS-304
Secondary Metabolites Isolation of Cryptocarya massoy and In Silico Study of its Anticancer Potency a Tasya Citra Violeta, b Reza Aditama, a Dikhi Firmansyah, c Wahyu Hidayat and a Lia Dewi Juliawaty* a Organic Chemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha no. 10, Bandung b Biochemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha no. 10, Bandung c Department of Forestry Faculty of Agriculture University of Lampung, Jl. Prof. Soemantri Brojonegoro No. 1 Gedung Meneng, Bandar Lampung Abstract The MAPK signaling cascade is one of the most frequently mutated and deregulated signaling pathways in leukemia cancer. MEK1 and ERK2 have been widely used as targets for inhibitor development, such as trametinib and ulixertinib. However, using those inhibitors may result in side effects such as coughing up blood to the point of causing prolonged bleeding from cuts. Therefore, alternative natural compound inhibitors are still to be made available. The Cryptocarya genus is one of the Indonesian plants reported to have significant anticancer properties, including against the murine leukemia P-388 cell line. Until now, research on the potential of Indonesian Cryptocarya secondary metabolites as MEK1 and ERK2 inhibitors has been limited. This research aimed to isolate secondary metabolites from the stem bark of C. massoy and study the potential of secondary metabolites from the stem bark of C. massoy as MEK1 and ERK2 inhibitors. The isolation of secondary metabolites from C. massoy was carried out in several steps, i.e., maceration of the stem bark powder with acetone solvent and separation of the acetone extract using chromatography methods, including vacuum liquid chromatography (VLC) and gravity column chromatography (GCC), to obtain pure compounds. The structure of the isolated compounds was determined using 1D NMR (1H-NMR and 13C-NMR). The results of the research indicated the presence of two compounds, namely (-)-syringaresinol, first discovered in the stem bark of C. massoy, but previously obtained from the wood of C. massoy, and also C-10 massoilactone, the main compound from C. massoy. The molecular docking analysis revealed that C-10 massoilactone from C. massoy had potency as MEK1 inhibitors with a docking score of -5,9 kcal/mol. In contrast, (-)-syringaresinol from C. massoy had the potency as ERK2 inhibitors with a docking score of -8,2 kcal/mol. Hydrophobic interactions were found to be important in the MEK1 and ERK2 inhibition mechanisms. Keywords: Cryptocarya massoy, MEK1, ERK2, anticancer, in silico, isolation Share Link | Plain Format | Corresponding Author (Tasya Citra Violeta)

20	CHEMISTRY AND MATERIAL SCIENCES	ABS-305
Effect of N-doped Carbon Quantum Dots (NCQDs) on NCQDs/TiO2/PVA Nanocomposites for Photocatalytic Degradation of Methylene Blue under Visible Light Rachmat Waluyo, Aljufri Hadju, Yolanda Rati, Yasni Novi Hendri, and Yudi Darma* Physics of Materials Electronics Research Group, Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Ganesha 10, Bandung 40132, Indonesia *yudi[at]itb.ac.id Abstract We study the effect of N-doped carbon quantum dots (NCQDs) on NCQDs/TiO2/PVA nanocomposites for photocatalytic degradation of methylene blue (MB) as a model pollutant dye under visible light irradiation. NCQDs were synthesized from Pangium edule (keluak) shells and urea as nitrogen-doped through a one-step heating reaction. The prepared NCQD has a diameter of 3.51 nm and photoluminescence emission centered at 445 nm. With the aim of producing an efficient and reusable catalytic system for wastewater treatment, NCQDs and TiO2 were incorporated into a PVA matrix and tested for their dye removal ability. NCQDs/TiO2/PVA nanocomposites were synthesized by solution casting method with different CDs concentration (1, 2, and 3 mL). FTIR and XRD results confirm the presence of PVA/TiO2/CDs in the nanocomposite. Moreover, the presence of NCQDs enhances photodegradation efficiency. We found that, the concentration of 2 mL of NCQDs on the NCQDs/TiO2/PVA nanocomposite became the most optimal catalyst with degradation efficiency up to 99.8% for 180 minutes under visible light irradiation and showed stability as a catalyst for MB degradation until 5 cycles. We can see that NCQDs/TiO2/PVA nanocomposites using this easy synthetic method have demonstrated efficient photocatalytic properties, offering an environmentally friendly and sustainable water remediation technology. Keywords: Water contamination- Dyes, Photocatalyst, NCQDs/TiO2/PVA nanocomposite, Keluak shell waste Share Link | Plain Format | Corresponding Author (Rachmat Waluyo)

21	CHEMISTRY AND MATERIAL SCIENCES	ABS-307
Identification of red, purple, and black pigment used in rock art from Sangkulirang sites, East Kalimantan using Raman spectroscopy Evi Maryanti (a*), Yana Maolana Syah (b), Pindi Setiawan (c), Grandprix. T.M. Kadja (d,e), Ismunandar (d) a) Department of Chemistry, Universitas Bengkulu, Bengkulu, Indonesia, 38371 *evi.maryanti[at]unib.ac.id b) Division of Organic Chemistry, Institut Teknologi Bandung, Bandung, Indonesia, 40132 c) Division of Visual Communication and Multimedia, Institut Teknologi Bandung, Bandung, Indonesia, 40132 d) Division of Inorganic and Physical Chemistry, Institut Teknologi Bandung, Bandung, Indonesia, 40132 e) Research Center for Nanosciences and Nanotechnology, Institut Teknologi Bandung, Bandung, Indonesia, 40132 Abstract Four pictorial panels from sites in the Sangkulirang area, East Kalimantan, which have unique prehistoric rock arts, have been studied using Raman spectroscopy. X-ray Fluorescence (XRF), Scanning Electron Microscopy, and Energy-dispersive X-ray spectrometry (SEM-EDS) were used as auxiliary techniques. The identification results show that the mineral hematite (alpha-Fe2O3) is used as a red, purple, and black pigment in the rock arts at the Jufri Cave, Lubang Suud, and Lubang Stefanus. However, apart from hematite, amorphous carbon was also identified in the black pigment material from the Bloyot Cave. Differences in Fe concentration, elemental composition, crystallinity, and particle size of hematite cause discrepancies in pigment hues in rock arts at the Sangkulirang sites. The presence of hematite as the main component of black pigment in rock art is new and has been reported for the first time. Keywords: Rock art, hematite, Raman spectroscopy, Sangkulirang sites Share Link | Plain Format | Corresponding Author (Evi Maryanti)

22	CHEMISTRY AND MATERIAL SCIENCES	ABS-52
Synthesis of Transition Metal (Co(^{+2}), Ni(^{+2}), Cu(^{+2})) Impregnated BiVO(_4) Photocatalys for Methylene Blue Degradation Irsya Nursyifa (a), Annisa Aulia Rahmah (a), Fainan Failamani (a), Bambang Prijamboedi (a*) a) Inorganic and Physical Chemistry Research Divison, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology Jalan Ganesha 10, Bandung 40132, Indonesia *prijamboedi[at]itb.ac.id Abstract Visible light driven photocatalysts have gathered enormous interest in recent years because of their capability to harness solar energy for chemical reaction. Bismuth Vanadate (BiVO(_4)) is a potential photocatalyst for various application since it has energy gap in the range of visible light. However, BiVO(_4) has high electron-hole recombination rate, poor charge transfer, thus it reduces the oxidation reaction kinetics. In this study, surface modification of BiVO(_4) by impregnation of Co(^{+2}), Ni(^{+2}) and Cu(^{+2}) ions were carried out to create charge carrier trap on the surface to reduce electon-hole recombination rate. BiVO(_4) photocatalysts were synthesized by hydrotermal method followed by impregnation with transition metal ions. The X-ray Diffraction (XRD) analysis showed that all samples are in single phase monoclinic scheelite structure. Further analysis reveals the increasing of crystallite size while lattice parameters are not affected by impregnation. The UV-Diffused Reflectance Spectroscopy (UV-DRS) characterization showed bandgap of 2,4 eV and it is also not affected by impregnation. Photoluminescence spectra do not show any additional peak with the impregnation. The effect of impregnation on photocatalytic performance was evaluated on the degradation of methylene blue (MB) under visble-light irradiation. Keywords: BiVO(_4), photocatalyst, surface modification, impregnation, methylene blue Share Link | Plain Format | Corresponding Author (Annisa Aulia Rahmah)

23	CHEMISTRY AND MATERIAL SCIENCES	ABS-309
CYCLIC DIARYLHEPTANOIDS FROM TWIGS OF MYRICA JAVANICA (MYRICACEAE) Vienntiny Safrilianti Effendi, Dikhi Firmansyah, and Lia Dewi Juliawaty* Organic Chemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung, 40132, Indonesia *Corresponding author, email: liadewi[at]itb.ac.id Abstract Keywords: Myrica javanica, cyclic diarylhepatanoid, murine leukemia P-388 cells. Share Link | Plain Format | Corresponding Author (Vienntiny Safrilianti Effendi)

24	CHEMISTRY AND MATERIAL SCIENCES	ABS-313
Synthesis, Molecular Formula and Thermal Stability of Hybrid Perovskites \( A_2SnBr_4 \) with \( A = C_4H_9NH_3^+ \) and \( C_5H_{11}NH_3^+ \) Selvi Anasha, Djulia Onggo and Muhamad A. Martoprawiro Inorganic and Physical Chemistry Division, Faculty of Mathematics and Natural Sciences Bandung Institute of Technology - ITB Abstract Hybrid perovskites are typical of smart materials that have been widely developed and applied as a photodetector material, solar cells and LED (Light Emitting Diode). 2D hybrid perovskites with the formula \( A_2MX_4 \) is formed by organic cation \( (A^+) \) and inorganic anion \( [MX_4]^{2-} \) usually uses divalent metal elements such as lead (Pb). Pb-based perovskite has good electronic properties but has high toxicity to the health and environments. In this research, we prepared lead-free hybrid perovskites \( A_2SnBr_4 \) with \( A^+ \) are butylammonium \( (C_4H_9NH_3^+) \) and amylammonium \( (C_5H_{11}NH_3^+) \). The synthesis was carried out by one-pot reaction of the reactants in the form of SnO, HBr, amine compounds and \( H_3PO_2 \) at room and elevated temperature \( 90^oC \). The yellow crystalline product was obtained under ambient light and green under ultraviolet light. Based on the elemental analysis, the products have the molecular formula of \( (C_4H_9NH_3)_2SnBr_4.HBr \) and \( (C_5H_{11}NH_3)_2SnBr_4.HBr \) with a reasonable yield of 54-72%. The thermal stability of butylammonium tetrabromotin(II) is \( 185^oC \) lower than amylammonium tetrabromotin(II) compound, \( 198^oC. \) Keywords: hybrid perovskites, \( (C_4H_9NH_3)_2SnBr_4.HBr, \) \( (C_5H_{11}NH_3)_2SnBr_4.HBr, \) one pot reaction, thermal stability Share Link | Plain Format | Corresponding Author (Selvi Anasha)

25	CHEMISTRY AND MATERIAL SCIENCES	ABS-60
Photocurrent Enhancement of Gold Nanoparticle Incorporated in ZnO as Electron Transport Layer in Hybrid Bulk Heterojunction Solar Cell Muhammad Cikal Merdeka (a*), Nur Fadhilah Syarif (a**), Priastuti Wulandari (a***) a) Physics of Magnetism and Photonic Research Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, West Java, Indonesia *cikalmerdeka[at]students.itb.ac.id **nurfadhilahsyarif[at]students.itb.ac.id ***pwulandari[at]itb.ac.id Abstract Organic solar cells are currently one of the most popular researches related to renewable energy because the devices produced are lighter, more flexible, cheaper to produce, and relatively easy to manufacture in comparison to solar cells with inorganic semiconductor crystalline materials. Various solar cell structures have been developed either by using organic-inorganic hybrids, donor-acceptor blends in bulk heterojunction structures, or using inverted configurations in an effort to improve the performance efficiency of the device. However, there are still some problem in development of organic solar cells such as low efficiency and stability of the device that comes from the photocurrent generation mechanism in the structure of organic solar cells. In this study, we investigate the effect of localized surface plasmon resonance (LSPR) from gold nanoparticles incorporated into the electron transport layer (ETL) of Zinc Oxide in order to enchance the performance of bulk-heterojunction solar cell. Synthesis of gold nanoparticles by capping 3-mercaptopropionic acid (AuMPA) was carried out by a modified reduction method following our previous method. TEM image shows the spherical shape of nanoparticles with a diameter size of ~51 nm. The absorbance spectra shows the surface plasmon peak of AuMPA in solution at ~527 nm. The fabrication of solar cells with the structure of ITO/ZnO:AuMPA/P3HT:PCBM/PEDOT:PSS/Ag was carried out using spin coating and thermal evaporation techniques. Incorporation of AuMPA into ZnAc solution was stable enough for AuMPA concentration in ZnAc less than 5 wt%. The fabricated solar cell reveals the enhancement in current density at short circuit condition (Jsc) from 13.5 mA/cm2 to 18.7 mA/cm2 with the addition of 0.88 wt% AuMPA in ZnAc solution along with the enhancement of power conversion efficiency (PCE) from 1.42% to 1.66% as characterized by J-V measurement. Upon further increasing the Au NPs content to 1.76 wt%, the device performance starts to decrease accompanied by decrease in both Jsc and Voc. Keywords: Gold nanoparticles- Hybrid bulk heterojunction solar cell- Localized Surface Plasmon Resonance (LSPR)- Zinc oxide (ZnO) Share Link | Plain Format | Corresponding Author (Muhammad Cikal Merdeka)

26	CHEMISTRY AND MATERIAL SCIENCES	ABS-317
Optical Properties of Carbon Dopped MoS2 Azrul Kiromil Enri Auni1, Indris Sarihon Sianturi1, Aljufri Hadju1, Jessie Manopo1, Fahdzi Muttaqien2,3, Yudi Darma1 * 1 Physics of Materials Electronics Research Group, Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Ganesha 10, Bandung, 40132, Indonesia 2 Instrumentation and Computational Physics Research Group, Department of Physics, Institut Teknologi Bandung, Jalan Ganesha No.10, Bandung, West Java 40132, Indonesia 3 Master Program in Computational Science, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha No.10, Bandung, West Java 40132, Indonesia *E-mail: yudi[at]itb.ac.id Abstract We study the optical properties of Carbon dopped (C-dopped) MoS2 by means of density functional theory and spectroscopic ellipsometry. Our theoretical model is a hexagonal type MoS2 (h-MoS2) with lattice parameters of a=3.189 A and c=12.384 A which are consistent with the experimental results. The calculated bandgap energy of pure h-MoS2 is 0.89 eV, while C-dopped h-MoS2 has lower bandgap energy, 0.17 eV. The carbon atoms is responsible for the reduced bandgap energy in the C-dopped h-MoS2 system. Furthermore, the dopant atom also shifts the peak of imaginary part of dielectric function from 1.90 eV to 0.27 eV, indicating the C-dopped h-MoS2 has wider optical absorption range. Experimentally, we fabricate the h-MoS2 with and without carbon doping using DC-Unbalanced Magnetron Sputtering at room temperature on SiO2/Si. These h-MoS2 systems have been characterized using XRD, SEM and EDX. The optical properties of pure h-MoS2 and C-doped h-MoS2 systems are being studied using spectroscopic ellipsometry and UV-Vis analysis. This research is very important to understand the effect of carbon doping on MoS2 and explore its potential application for future devices. Later Keywords: MoS2- carbon doping- optical properties- DFT- sputtering Share Link | Plain Format | Corresponding Author (Azrul Kiromil Enri Auni)

27	CHEMISTRY AND MATERIAL SCIENCES	ABS-63
Characteristic and Performance Study of of Dye Sensitized Solar Cell (DSSC) Using Natural Dye of Red Dragon Fruit Extract Shofy Zahrotul Aghniya (a*), Setiya Rahayu (a**), Priastuti Wulandari (a***) a) Physics of Magnetism and Photonic Research Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung Jalan Ganesha 10, Bandung 40132, Indonesia *shofy_zahrotul_aghniya[at]students.itb.ac.id **setiya.rahayu[at]students.itb.ac.id ***pwulandari[at]itb.ac.id Abstract Dye Sensitized Solar Cell (DSSC) is a third generation solar cell that uses dye as a sensitizer to absorb the light when it irradiate the device. The most widely used dyes are Ruthenium-based dyes, such as N-719, N-3, Z-907 with the resulting device performance efficiency above 10%. In recent years, many researchers have begun to study dyes using natural materials such as fruits and vegetables to replace the Ruthenium dye due to the difficulty in material manufacturing process and the high material cost. One of the natural dyes that has been widely studied is red dragon fruit or Selenicereus Undatus. From previous studies, it was found that red dragon fruit extract has absorbance area that is almost similar to dye N-719 even the performance of red dragon fruit-based DSSC devices is still being investigated. For this reason, a simple study was carried out regarding the optical and chemical characteristics of red dragon fruit dye and optimizing the use of natural red dragon fruit dye in the DSSC device. The research method consist of experimental preparation of red dragon fruit extract dye solution and DSSC fabrication. The results of UV-Vis characterization show that the absorbance area of the red dragon fruit dye solution is in the visible light region (400 nm to 600 nm) which is expected to absorb more visible wavelength range. From the results of the Taut Plot calculation by used of absorbance spectrum data, it is found that the energy band for red dragon fruit is 1.9 eV. Meanwhile, the results of FTIR characterization in dragon fruit dye is found the presence of anthocyanin and betalain pigments which are relate to light absorption and its chemical interactions with the TiO2 layer in the DSSC structure. In our study, the performance of dragon fruit extract dye-based DSSC devices have shown the J-V solar cell profile even the efficiency is still lower in comparison to Ruthenium dye-based DSSC. Keywords: Dye Sensitized Solar Cell- red dragon fruit- Fourier Transform Infrared spectroscopy- UV-Vis spectroscopy- J-V measurement Share Link | Plain Format | Corresponding Author (Shofy Zahrotul Aghniya)

28	CHEMISTRY AND MATERIAL SCIENCES	ABS-321
SYNTHESIS OF PHENOLIC BODIPY-BASED FLUORESCENT SENSOR FOR DETECTION OF ANTHRACENE Lenggah Purwandari(1,) Muhammad Yudhistira Azis(2), Dikhi Firmansyah(1*) 1) Organic Chemistry Division, Bandung Institute of Technology, Jalan Ganesha 10, Bandung, 40132, Indonesia. 2) Analytical Chemistry Research Group, Bandung Institute of Technology, Jalan Ganesha 10, Bandung, 40132, Indonesia. Abstract PAH exposure in ambient air comes from tobacco, smoke, and vehicle exhaust emissions. Due to their carcinogenic properties, it needs to be monitored. Anthracene (ANT) is tricyclic PAH on the EPA^s priority polutan lists, it is ubiquitous in the atmosphere and aqueous media. Despite its very low solubility in water (0,04 mg/L), it remains a highly toxic micropollutant. Previously, Boron-dipyrromethene (BODIPY)-PAH interaction was reported. Compared to phenyl BODIPY, phenolic BODIPY showed better fluorescent sensing for PAH. In this research, we synthesized phenolic-BODIPY (i.e., vanillin-BODIPY) to further study the interaction.1H NMR and 13C NMR studies were carried out to investigate the structure of BODIPY. Isosbestic absorption points were obtained on anthracene titration with vanillin-BODIPY (362 nm, 369 nm, 379 nm) and fluorescence studies of anthracene addition to vanillin-BODIPY showed an increased intensity. These results indicate a weak interaction that led to a fluorescence enhancement in a linear fashion, showing phenolics BODIPY could be a potential candidate for fluorescence anthracene sensors. Keywords: Phenolic-BODIPY, Anthracene interaction, Fluorescence, Chemical sensors Share Link | Plain Format | Corresponding Author (Lenggah Purwandari)

29	CHEMISTRY AND MATERIAL SCIENCES	ABS-73
The effect of an external AC electric field on the solidification process of Ca(NO3)2.4H2O : a preliminary study Akhmad Yusuf, Yunita Anggraini, Daniel Kurnia, Inge Magdalena Sutjahja Dept. of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha No. 10, Bandung 40132 Abstract Calcium nitrate tetrahydrate, Ca(NO3)2.4H2O (abbreviated as CaNT), is an inorganic phase change material with a melting point of 44 C. It can be used for various applications in the medium temperature range of thermal energy storage (TES). However, the main disadvantage of inorganic phase change materials is the high supercooling degree caused by the high barrier energy during the solidification process. There are many ways to reduce this energy barrier, and one method is applying an electric field. This paper describes a preliminary study of the effect of an external AC electric field on the solidification process of CaNT. The electric field is applied using a copper plate electrode with a voltage and frequency of 220 Volts and 50 Hz, respectively. The statistical analysis results show that the external AC electric field can reduce the freezing time and supercooling time, making the phase transition sharper. This study is essential to optimize the material performance as a latent TES Keywords: external AC electric field, Ca(NO3)2.4H2O, solidification Share Link | Plain Format | Corresponding Author (akhmad yusuf)

30	CHEMISTRY AND MATERIAL SCIENCES	ABS-331
Colorimetric Sensing of Zinc Ions Based of Dipyrrin Derivate Ayu Tri Khodizah (a), Mohammad Akbar Ferryansyah (a), Lia Dewi Juliawaaty (a), Didin Mujahidin (a), Brian Yuliarto (b),(c), Anas Santria (d),(e), Dikhi Firmansyah(a*) (a)Organic Chemistry Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung, 40132, Indonesia. *dikhfi[at]itb.ac.id (b)Advanced Functional Materials (AFM) Laboratory, Engineering Physics, Institut Teknologi Bandung, 40132, Bandung, Indonesia. (c)Research Center for Nanosciences and Nanotechnology (RCNN), Institut Teknologi Bandung, 40132, Bandung, Indonesia (d)Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan. (e)Research Center for Chemistry, National Research and Innovation Agency, Kawasan Puspitek, Serpong, Tangerang Selatan, Banten, Indonesia Abstract Vanillin&#8210-dipyrrin was described as a colorimetric chemosensor for zinc ions based on the formation of complexes. The interaction between vanillin-dipyrrin ligand and zinc ions resulting in the formation of the zinc-vanillin&#8210-dipyrrin complex compound with a ratio of 1:2. This complex showed high linearity of 0.98 (at 0-0.5 zinc ions eq.) and 0.99 (at 0.5-1 zinc ions eq.) indicating a good quantitative measurements potential. The UV-Vis spectroscopic studies demonstrated that the addition of zinc ions to vanillin-dipyrrin in methanol resulted in a change in the UV-Vis spectra from the initial absorption maxima of 428 and 552 nm to 480 nm, accompanied by a color change from pink to orange. Keywords: vanillin-dipyrrin- zinc ions- UV-Vis studies- colorimetric Share Link | Plain Format | Corresponding Author (Ayu Tri Khodizah)

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