Synthesis, Characterization, and Application of Fe3O4/Cdots for Rhodamine B Degradation: Variation of Scavenger Types Lina Mahardiani (a*), Dwi Safitri (a)
Chemistry Education, Universitas Sebelas Maret, Surakarta, Central Java, 57126, Indonesia
Abstract
This research aims to: (1) determine the synthesis process of Cdots, Fe3O4, and Fe3O4/Cdots as photocatalysts- (2) determine the characteristics of Cdots, Fe3O4, and Fe3O4/Cdots- and (3) analyze the effect of different scavengers on the photocatalytic reaction of Cdots, Fe3O4, and Fe3O4/Cdots on Rhodamine B dye. The research was conducted by experimental method in the laboratory with the following steps: (1) preparation of crude extract from ruku-ruku leaves- (2) green synthesis of Fe3O4- (3) green synthesis of Cdots- (4) preparation of Fe3O4/Cdots- (5) characterization- (6) photocatalytic application on Rhodamine B. The results showed that: (1) Cdots, Fe3O4, and Fe3O4/Cdots were successfully synthesized. Fe3O4 was synthesized with the precusors of crude extract of ruku-ruku leaves, FeCl3⋅-6H2O, and FeSO4⋅-7H2O, resulting in a brown color and magnetic properties. Cdots were successfully synthesized with precursors of pineapple peel filtrate, ethanol and demineralized water, yielding a yellowish-brown solution. Fe3O4/Cdots were synthesized by combining Cdots with Fe3O4 through an ultrasonic method, resulting in a brown powder. (2) The crystallinity degrees of Fe3O4 and Fe3O4/Cdots were 66.69% and 68.91%, with crystal sizes of 70.90 and 67.67 nm. The surface areas were 49.26 and 51.62 m2/g, and the band gaps were 1.84 and 1.86 eV. Based on SEM images, Fe3O4 has irregular morphology with agglomeration and rough surface, while Fe3O4/Cdots displayed a smoother surface and a more uniform distribution of smaller particles. (3) The addition of H2O2 to Cdots, Fe3O4 and Fe3O4/Cdots photocatalysts resulted in percent degradation of 50.85%, 94.48% and 87.06% at 10 ppm RhB concentration and 120 min contact time. (4) From the regeneration results of Fe3O4 and Fe3O4/Cdots the percent degradation at the 5th regeneration was 75.07% and 59.72%. Therefore, Fe3O4 and Fe3O4/Cdots are effective for reuse.
Keywords: Photocatalytic, Cdots, Fe3O4, Fe3O4/Cdots, Rhodamine B
