ABSTRACT

A novel g-C₃N₄/ZnO-TiO₂ nanocomposite was prepared by facile calcination and hydrothermal assisted route to boost the photocatalytic efficiency of g-C₃N₄. The structural, morphology and optical properties of as-obtained nanocomposites (NCs) were examined by various physicochemical methods such as XRD, FT-IR, FESEM-EDX, HR-TEM, UV-DRS and PL spectra relatively. The as-obtained g-C₃N₄/ZnO-TiO₂ heterojunction NCs displays an optimum efficiency (93.6%) and high photo-degradation rate constant towards the photo-degradation of RhB dye in 75 min under visible-light exposure. Likewise, the synergistic effects on heterostructure strong-coupling interfaces assembly of g-C₃N₄ and TiO₂/ZnO NPs, which facilitates the excellent photo-excited charge separation efficiency, suppressing the recombination rate and also widening the visible-light fascination ability. Hence, the resulting in a prolonged lifetime leading to continuous generation of h⁺ and ^•OH⁻ species which were eventually improved the photo-degradation process. Also, the as-obtained hybrid g-C₃N₄/ZnO-TiO₂ photocatalysts (PCs) revealed superior recycling stability. Moreover, a probable photocatalytic reaction mechanism of the novel PCs was also suggested.

摘要

为了提高gC 3 N 4 的光催化效率，通过简易煅烧和水热辅助途径制备了_一种新型_gC 3 _N 4 _/ ZnO-TiO ₂纳米复合材料。通过XRD、FT-IR、FESEM-EDX、HR-TEM、UV-DRS和PL光谱等多种物理化学方法对所获得的纳米复合材料（NCs）的结构、形貌和光学性质进行了比较研究。得到的gC ₃ N ₄ /ZnO-TiO ₂异质结 NCs 在可见光照射下 75 分钟内对 RhB 染料的光降解表现出最佳效率 (93.6%) 和高光降解速率常数。_{同样，gC 3} N ₄和 TiO ₂ /ZnO NPs对异质结构强耦合界面组装的协同作用，有利于获得优异的光激发电荷分离效率，抑制复合率，并扩大可见光的吸引能力。因此，导致寿命延长，导致 h ⁺和^• OH ^-物质的连续产生，最终改善了光降解过程。此外，所获得的杂化 gC ₃ N₄ /ZnO-TiO ₂光催化剂（PCs）显示出优异的再循环稳定性。此外，还提出了一种可能的新型 PC 的光催化反应机理。