杂化Cu2O/Cu纳米粒子的水相合成及强化光降解甲基橙的催化活性研究

为了优化Cu2O纳米粒子的光催化性能，论文以抗坏血酸作为还原剂、聚乙烯吡咯烷酮为表面活性剂采用水相合成的方法通过调控反应温度制备出杂化Cu2O/Cu纳米粒子。利用SEM、XRD和N2吸附技术对Cu2O/Cu纳米粒子的形貌特征和结构性能进行表征。同时，也研究Cu2O/Cu纳米粒子催化降解甲基橙(MO)的效果和降解反应动力学。实验结果表明，制备的杂化Cu2O/Cu纳米粒子为“鹅卵石”形状，粒径尺寸范围在20至40nm之间，与纯Cu2O粒子相比相比，杂化Cu2O/Cu粒子具有尺寸小、比表面积大的特点。由于杂化材料中引入了Cu纳米粒子，促进了Cu和Cu2O和之间的界面电荷转移，使得Cu2O/Cu纳米粒子展现更优异的催化性能。Cu2O/Cu催化降解MO的反应符合一级动力学反应模型。经过四次循环使用后，杂化Cu2O/Cu仍然能表现出良好的催化活性。

Enhanced photocatalytic activity of Cu2O/Cu heterogeneous nanoparticles synthesized in aqueous colloidal solutions on degrada

Heterogeneous Cu2O/Cu nanoparticles are synthesized by colloidal chemistry approach using ascorbic acid as a reducing agent and polyvinylpyrrolidone as a surfactant. Morphology and structure of Cu2O/Cu nanoparticles are analyzed by SEM, XRD and N2 sorption technique. The catalytic performances of Cu2O/Cu nanoparticles for the degradation of methyl orange (MO) are investigated and reaction kinetics of MO degradation is also studied. The results show heterogeneous Cu2O/Cu nanoparticles display cobblestone-like morphology with ranging from 20 to 40 nm, which are slightly smaller in particle size and higher in BET surface areas than those of pure Cu2O. The Cu2O/Cu nanoparticles demonstrate good potential on degradation of MO because Cu nanoparticles in the Cu2O/Cu hererostructures promote the interfacial charge-transfer kinetics between Cu and Cu2O. High initial MO concentration not only produces low degree of MO degradation, but also increases the reaction time to reach equilibrium, and the degradation reactions follow the pseudo-first-order kinetics model. The Cu2O/Cu catalyst still demonstrates good catalytic activity after four photodegradation cycles of MO solutions.