Zn_(0.8)Cd_(0.2)S-乙二胺杂化固溶体光催化剂的制备及其催化制氢性能

Preparation of Zn_(0.8)Cd_(0.2)S-Ethylenediamine Hybrid Solid Solution Photocatalysts and Their Hydrogen Production Performance

采用溶剂热法制备了具有不同厚度和大小的Zn_(0.8)Cd_(0.2)S-乙二胺(En)杂化纳米片固溶体,考察了制备过程中S/(Zn+Cd)摩尔比对所制备光催化材料的组成与结构、光电性质以及亲水性能的影响。研究表明,随着制备体系中硫脲含量的增加,固溶体纳米片表面逐渐平整;合适的S/(Zn+Cd)摩尔比可以提高光催化材料光生电子和空穴的分离效率。光催化性能评价表明,制备过程中的S/(Zn+Cd)原子比对其制氢活性有明显影响,在可见光照射下,S/(Zn+Cd)为4.75时,合成的Zn_(0.8)Cd_(0.2)S-En样品表现出最高的H_2产率,可达12100μmol·h^(-1)·g^(-1)。光催化活性的提高与样品较少的表面缺陷、合适的形貌以及高光生电子和空穴分离效率有关。

The titled hybrid solid solutions with different thickness and size were successfully synthesized by changing the atomic ratio of S/（ Zn ＋ Cd） in the hydrothermal reaction. The results showed that the content of thiourea amount in solvent has an important effect on the composition and structure,photoelectric property and hydrophilic property of the prepared solid solutions. With the increase of thiourea amount in the reaction system,the nanosheet solid solutions were gradually formed. Fluorescence emission spectra（ photoluminescence spectra） and photocatalytic activity tests showed that the proper S/（ Zn ＋ Cd） atomic ratio can improve the separation efficiency of photogenerated electrons and holes,resulting in the superior photocatalytic activity. Under visible light irradiation,the titled solid solution exhibites the highest hydrogen yield of 12100μmol·h-1·g-1 at S/（ Zn ＋ Cd） of 4. 75. The improved photocatalytic activity is mainly related to the less surface defects,suitable morphology,and high separation efficiency of photo-generated electrons and holes.