光沉积制备PtO_(2)/ZnO纳米复合材料及催化性能研究

Photo-deposition preparation and catalytic performance of PtO_(2)/ZnO nanocomposites

目的:研究制备一种高效稳定的纳米催化剂来降解对硝基苯酚。方法:采用水热法制备直径500~1000 nm ZnO纳米棒,利用ZnO半导体的光化学特性,在氙灯照射下,诱导氯铂酸溶液中的Pt^(4+)离子原位沉积在ZnO纳米棒上制得PtO_(2)/ZnO纳米复合材料。改变氯铂酸溶液的添加量和光照时间来调控PtO_(2)纳米粒子的生长情况。结果:随着PtO_(2)负载量的增多,催化效率越高,氯铂酸的添加量为4 mL时,催化速率最高为1.85 min^(-1);当负载量相同时,光照时间的提高也可以显著提高其催化效果。结论:本实验制备的PtO_(2)/ZnO表现出了优异的催化速率,而且该催化剂性能稳定,8次重复使用实验中,5 min内对硝基苯酚的降解率均在95%以上。

Aims:The paper aims to prepare and report an efficient and stable nano-catalyst for the reduction of p-nitrophenol.Methods:ZnO nanorods with diameters of 500~1000 nm were prepared by the hydrothermal method.Then Pt 4+ions were in situ deposited and PtO_(2)/ZnO nanocomposites were obtained under Xenon lamp irradiation.The effects of the amount of chloroplatinic acid solution and the light time on the growth of PtO_(2) nanoparticles were investigated.Results:The catalytic efficiency of PtO_(2)/ZnO nanocomposites increased with the enhancement of PtO_(2) loading.When the addition amount of chloroplatinic acid was 4 mL,the maximum catalytic rate constant was 1.85 min^(-1).Under the same loading amount,the catalytic efficiency improved significantly with the increase of light time.Conclusions:The PtO_(2)/ZnO in this work showed an excellent catalytic performances and good stability.The PtO_(2)/ZnO nanocomposites showed high degradation rate(>95%)up to eight cycles.