溶胶-凝胶法和高分子网络凝胶法合成光催化ZnO纳米晶的比较研究

通过对比溶胶-凝胶法和高分子网络凝胶法合成的ZnO纳米晶的微结构和光催化活性来探讨不同制备方法对光催化剂的影响,用XRD、TEM、SEM、XPS和PL对所制备样品的晶体结构、形貌、化学成分和光学特性进行了研究。结果表明,随着温度的升高,两种方法制备的样品其晶粒尺寸都增大,颗粒团聚现象改善,化学吸附氧浓度增大,缺陷减少,结晶性变好。比较发现,煅烧温度为650℃,采用高分子网络凝胶法制备的光催化剂的光催化效果更好。分析认为,高分子网络凝胶法更适合ZnO光催化剂的合成。

Comparative Study on the Synthesis of ZnO Nanocrystals by Sol-gel and Polymer Network Gel Method

Effect of different synthetic methods (polymer gel network and sol-gel) on the microstructures and photocatalytic activities of ZnO nanocrystals was studied by XRD, TEM, SEM, XPS and PL.The results show that the grain size of samples obtained by both methods increases with the increase in temperature, this leads to the reduced particle aggregation and defect for better crystallinity.By comparison, it is found that the samples calcinated at 650 ℃ by polymer gel network process exhibit the higher photocatalytic activity, which is attributed to the better crystallinity, more uniform particle distribution, larger specific surface area in the case of keeping high-concentration Chemical adsorption of oxygen.As such, polymer gel network process is a more suitable method in the synthesis of ZnO photocatalyst.