Cu2O/Cu2S 复合材料制备及可见光催化降解甲基橙的研究

通过水热法制备Cu₂O/Cu₂S 复合材料对甲基橙(MO) 进行光催化降解实验。在Cu₂O 中引入S 元素, 通过 改变Cu/S 投加摩尔比, 从而得到不同Cu/S 的复合材料。利用XRD、SEM、UV-vis、EIS 等手段对材料进行表征, 并 对MO 进行光催化降解实验。XRD 结果表明, 随着S 含量的增多, Cu₂S 的衍射强度逐渐上升, Cu₂O 的f111g 晶面 衍射强度逐渐降低。SEM 结果表明Cu₂S 能较好地包覆在Cu₂O 八面体的表面。通过UV-vis 和EIS 结果计算得知, 复合材料带隙为1.49 eV, 电荷转移电阻大幅降低。降解实验结果表明复合材料最佳Cu/S 投加摩尔比为15 : 1, 其在 100 min 时对MO (100 mL, 10 mg/L) 降解率达到91.4%, 明显高于纯Cu₂O 对于MO 的降解率(60.3%)。猝灭实验表 明了?OH 和 ?O₂ ^-在光催化过程中起到主要作用。

Preparation of Cu2O/Cu2S Composite and Study on Visible Photocatalytic Degradation of Methyl Orange

Photocatalytic degradation of methyl orange (MO) by Cu₂O/Cu₂S composite material prepared by hydrothermal method was studied. By introducing S element into Cu₂O and changing the molar ratio of Cu/S, different Cu/S composites were obtained. The materials were characterized by XRD, SEM, UV-vis and EIS, and photocatalytic degradation of MO was carried out. XRD results show that with the increase of S content, the diffraction intensity of Cu₂S increases gradually, while the diffraction intensity of f111g plane of Cu₂O decreases gradually. SEM results show that Cu₂S can coat the surface of Cu₂O octahedron well. According to UV-vis and EIS results, the band gap of the composite is 1.49 eV, and the charge transfer resistance is greatly reduced. The results of degradation experiments show that the optimum Cu/S molar ratio is 15 : 1, and the degradation rate of MO (100 mL, 10 mg/L) reaches 91.4% at 100 min, which is significantly higher than that of pure Cu₂O (60.3%). The quenching experiments show that ?OH and ?O₂^- play a major role in the photocatalytic process.