CQDs／TNS复合光催化剂的制备及其可见光催化活性

摘要

In this paper ,the carbon quantum dots (CQDs) were synthesized by the hydrother‐mal method with gelatin as raw material and polyethylene glycol (PEG) as modification agent . CQDs and titania nanosheets(TNS) were refluxed in ethanol solution to form CQDs/TNS com‐posite photocatalysts .The CQDs/TNS composite photocatalysts were characterized by XRD , HRTEM ,FT‐IR and XPS .The results indicated that the obtained CQDs with the average size of about 4 nm showed good fluorescence and upconversion fluorescence properties .CQDs/TNS photocatalysts exhibited better photocatalytic activities for RB degradation under visible light irradiation than that of bare TNS ,in which CQDs/TNS‐7 5.% had the best photocatalytic activ‐ity and excellent recycling performance after 3 times .It is concluded that the superior photocat‐alytic activity of CQDs/TNS composite photocatalysts might arise from the high‐dispersed CQDs on TNS via tightly bonding due to its unique up‐conversion fluorescence of CQDs and the high activity facet {001}of TNS .%以明胶为原料用水热法一步合成了碳量子点（CQDs），经过聚乙二醇表面修饰后，在乙醇溶液中与二氧化钛纳米片（TNS）复合形成了碳量子点高分散负载的CQDs／TNS 复合光催化剂．对复合光催化剂进行了XRD、FT‐IR、HRTEM和XPS表征，结果表明合成的碳量子点的平均粒径为4 nm且具有较好的荧光性能．与纯TNS相比，CQDs／TNS复合光催化剂在可见光下对罗丹明B表现出很好的光催化降解活性．当CQDs／TNS复合光催化剂中CQDs含量为75．％时光催化活性最好，并且在3次循环降解后活性仍保持不变．其优异的光催化活性来自于碳量子点的独特上转换荧光性能和二氧化钛纳米片高活性｛001｝晶面的共同作用．