Efektivitas Nanokomposit ZnO/N-Doped Carbon Nanodots sebagai Fotodegradasi Rhodamin B di Bawah Radiasi Sinar UV

Abstract

The textile industry in Indonesia is experiencing very rapid development. One of the liquid wastes that are usually produced by the textile industry is Rhodamin B. Therefore, a method is needed to degrade Rhodamin B (RhB), namely by photodegradation. Photodegradation can be carried out using ZnO nanoparticles, N-CNDs, and ZnO/N-CNDs nanocomposites. Combining ZnO with N-CNDs to form nanocomposites can enhance charge transfer in photocatalysis. In this study, the synthesis of photocatalyst materials for N-CNDs, ZnO, and ZnO/N-CNDs nanocomposites has been successfully carried out. The research was carried out in several stages. In the first stage, the synthesis of N-CNDs was carried out using molasses as a precursor and urea as nitrogen doping using the microwave method. In the second stage, the synthesis of ZnO nanoparticles and ZnO/N-CNDs nanocomposites was carried out using the sonochemical method. Furthermore, photodegradation of RhB used ZnO/N-CNDs nanocomposites with variations in irradiation times of 30, 60, 90, 120, and 150 minutes. Then photodegradation of RhB using ZnO nanoparticles and N-CNDs under UV irradiation during the irradiation time with the highest % degradation. Furthermore, the characterization of the photocatalyst and RhB materials was carried out after being degraded. The results of this study indicated that N-CNDs had been successfully synthesized which was confirmed from TEM results, which showed that N-CNDs were spherical in shape with a particle size of 3.5 nm, had a blue glow under a 395 nm UV lamp, and an absorbance spectrum at 246 nm. ZnO nanoparticles produced a particle size of 64,2 nm and an absorbance spectrum at 380 nm. The ZnO/N-CNDs nanocomposite has a particle diameter of 5.7 nm, and has an absorbance spectrum of 281 nm. The results of the biodegradation analysis showed that the % degradation of RhB in the ZnO/N-CNDs nanocomposite was obtained for 150 minutes of irradiation with the highest % degradation of 73.6% and the results of photodegradation of RhB using N-CNDs and ZnO nanoparticles for 150 minutes obtained the percentage of degradation namely respectively 11% and 43%. It was concluded that the highest photodegradation effectiveness was in the ZnO/N-CNDs nanocomposite for 150 minutes under UV ligh