Phases evolution and photocatalytic activity of Cu2O films electrodeposited from a non-pH-adjusted solution

A pure-phase Cu2O film photocatalyst was successfully prepared by the electrodeposition technique from a non-pH-adjusted solution. To investigate the phase evolution and photocatalytic activity of the film, the electrodeposition was conducted at different deposition temperatures. Photocatalytic activity of the films was evaluated from methylene blue (MB) dye degradation. The Cu2O phase initially appeared at room temperature and its fraction was found to increase with increasing the deposition temperature, while the impurity phase was successfully diminished. A pure Cu2O film with a narrow optical bandgap energy of 1.96 eV was obtained at 75°C. The multi-faceted crystals were found to form at 45°C and became a truncated octahedral structure that possessed {111} and {100} facets as deposition temperature further increased. A preferred orientation growth of {110} facet, which is known to possess a relatively high surface energy, was produced at 75°C. The performance of MB photodegradation ..., The data were obtained through UV-Visible spectrophotometer measurements conducted within the wavelength range of 500-750 nm.,本研究通过电沉积技术，在未调节pH值的沉积溶液中成功制备出纯相氧化亚铜（Cu₂O）薄膜光催化剂。为探究该薄膜的相演变规律与光催化活性，实验在不同沉积温度下开展电沉积过程。以亚甲基蓝（MB）染料降解性能作为评价该薄膜光催化活性的指标。室温下即可生成氧化亚铜相，且其占比随沉积温度升高不断提升，同时杂相被有效消除。在75℃条件下可获得光学带隙仅为1.96 eV的纯相氧化亚铜薄膜。在45℃时可形成多面体形晶体，随着沉积温度进一步升高，晶体演变为暴露{111}与{100}晶面的截角八面体结构。在75℃时，薄膜会出现{110}晶面的择优生长——该晶面因具有相对较高的表面能而被广泛报道。亚甲基蓝光降解性能……相关测试数据均通过紫外-可见分光光度计在500~750 nm波长范围内测得。