雪花状Cu2S/缺陷型UiO-66 p-n异质结用于光催化还原Cr(VI)

为了解决金属-有机骨架材料Ui O-66可见光响应差、电子-空穴复合快的问题，以雪花状Cu₂S为基材，对Ui O-66进行缺陷调控，采用溶剂热法制得Cu₂S/缺陷型Ui O-66 p-n异质结型复合光催化剂。以K₂Cr₂O₇溶液为目标污染物，分析其对Cr(Ⅵ)的光催化还原能力。SEM、XRD和XPS结果证明，缺陷型UiO-66在雪花状Cu₂S上均匀生长。莫特-肖特基曲线证明，在Cu₂S与缺陷型UiO-66界面处形成了紧密的p-n异质结，提高了材料对可见光的利用率，促进了光生电子-空穴对的有效分离。在模拟可见光照射下，20 mg 50%Cu₂S/缺陷型Ui O-66复合光催化剂(50%为缺陷型UiO-66的负载量，以生成的Cu₂S质量计)对50 mL质量浓度为20 mg/L的K₂Cr₂O₇溶液的还原率高达98.92%，且循环5次...

Snowflake Cu2S/defective UiO-66 p-n heterojunction for photocatalytic reduction of Cr(VI)

To solve the problems of poor visible light response and rapid electron-hole recombination of metal-organic skeleton material UiO-66, snowflake Cu2S was used as the substrate for the defect control of UiO-66, as a result, Cu2S/defective UiO-66 composite photocatalyst with p-n heterojunction was prepared by solvothermal method. The photocatalytic reduction of Cr(VI) in K2Cr2O7 solution was investigated. The results of SEM, XRD and XPS showed that the defective UiO-66 grew uniformly on Cu2S. A tight p-n heterojunction between Cu2S and defective UiO-66 was formed, which improved the utilization rate of the material to visible light and promoted the effective separation of photogenerated electron-hole pairs. Under visible light irradiation, the reduction rate of 20 mg 28% Cu2S/defective UiO-66 composite photocatalyst (28% is loading amount of defective UiO-66, based on the mass of generated Cu2S) for 50 mL 20 mg/L K2Cr2O7 solution reached to 98.92%, as well as the reduction rate of Cr(VI) still reached 96.27% after 5 cycles. The synergistic effect of defect regulation and heterojunction construction can not only effectively solve the problem of easy agglomeration of defective UiO-66 nano-catalyst, but also improve the photocatalytic reduction performance of UiO-66.