A novel photocatalyst of Y2O3-BaO-ZnO ternary system for enhanced photocatalytic degradation of carbofuran insecticide

A novel Y2O3-BaO-ZnO ternary system was synthesized via precipitation of a mixture of Y(NO3)3.6 H2O:Ba(NO3)2:Zn(NO3)2.6 H2O using some Fibonacci sequences. The Y2O3-BaO-ZnO was applied to the photocatalyst to investigate the degradation of carbofuran insecticide. The Y2O3-BaO-ZnO prepared at the sequence ratio of 5:8:13 (YBZ5) exhibited the highest photocatalytic performance. Morphological characterization showed that the particle size of the YBZ5 sample was significantly smaller than that of ZnO by over half, possibly providing high surface areas. The crystalline structure, functional group, and surface chemical composition investigations confirmed the presence of Y2O3, BaO, and ZnO. The fluorescence study exhibited no difference. Based on band gap energy and energy band alignment analysis, the Y2O3-BaO-ZnO ternary system demonstrated a well-aligned valence band. The energy band alignment analysis revealed a good alignment of the valence band for continuous hole transport in the Y2O3-BaO-ZnO ternary system. The alignment induces charge separation which reduces recombination and provides efficient active carriers at the surfaces of the photocatalyst, allowing reactions with toxic molecules. Therefore, the synergistic function of high surface areas and appropriate energy band alignments of the novel Y2O3-BaO-ZnO ternary system is considered the crucial factor in the enhancement of photocatalytic performance.