Cu2O@ZnO复合光催化剂对难生物降解有机物的光降解

通过改进的浸渍-还原-空气氧化法成功制备了Cu₂O@ZnO复合光催化剂，考察Cu₂O@ZnO对对硝基苯酚（PNP）和聚丙烯酰胺（PAM）2种不同化学结构污染物的光催化效果，同时探究了催化剂的稳定性和降解机制.结果表明，在模拟太阳光照射下，当铜锌物质的量比为0.15时，Cu₂O@ZnO复合光催化剂具有最佳的光催化降解性能，其中对硝基苯酚的光催化降解率为98.2%，聚丙烯酰胺光催化降解率为99.7%.基于X射线衍射（XRD）、X射线光电子能谱（XPS）、光致发光（PL）光谱、紫外-可见（UV-Vis）吸收光谱等表征手段可以推断，Cu₂O和ZnO形成Ⅱ型异质结，有效地抑制光生电子空穴对的复合.自由基捕获实验指出超氧自由基和空穴为主要活性物种，经过4次循环使用后光催化剂仍具有很高的光催化性能.

Photodegradation of refractory organic compounds by Cu2O@ZnO composite photocatalyst

Cu₂O@ZnO composite photocatalyst was successfully prepared by improved impregnation-reduction-air oxidation method, and the photocatalytic activity and degradation mechanism of the Cu₂O@ZnO was investigated by the degradation of two different chemical pollutants (p-nitrophenol (PNP) and polyacrylamide (PAM)). Cu₂O@ZnO composite photocatalyst expressed the best photocatalytic degradation performance under the simulated sunlight when the molar ratio of copper to zinc was 0.15, the photocatalytic degradation rates of p-nitrophenol and polyacrylamide arrived at 98.2% and 99.7%, respectively. The results of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL), ultraviolet-visible (UV-Vis) absorption spectroscopy and so on showed that Cu₂O and ZnO formed type Ⅱ heterojunction, then the recombination of photogenerated electron hole pairs was inhibited effectively. Superoxide radicals and holes were the main active species by free radical trapping experiments, and the photocatalyst still expressed high photocatalytic activity after four cycles of reaction.