大规模合成非贵金属磷化物/CdS复合光催化剂高效可见光催化产氢（英文）

目前,在可见光照射下光催化产氢是一条解决能源短缺的理想途径.该途径实现工业化的两个关键因素是得到低成本的光催化剂和高的产氢效率.非贵金属助催化剂代替贵金属可大大降低光催化剂的成本.通过简单的方法大规模合成并组装半导体和非贵金属助催化剂以形成复合光催化剂可进一步降低成本.本文采用大规模和低成本的共沉淀法合成了磷化物/CdS光催化剂,实现了光催化产氢.当负载CoP和Mo P助催化剂后,光催化产氢活性得到大幅度提高.其中CoP/CdS和Mo P/CdS的最佳产氢量分别为140和78μmol/h,并分别为CdS的7.0倍和4.0倍,分别为Pt/CdS的2.0倍和1.1倍.这说明磷化物CoP和Mo P是具有优良催化活性的低成本非贵金属助催化剂,可以代替贵金属助催化剂应用在光催化产H_2中.在制备磷化物/CdS时,先将两种磷化物反应原料分别在水热反应釜和马弗炉中煅烧合成前驱体,再分别在管式炉氮气和氢气氛围中进行磷化得到磷化物Mo P和CoP.然后,将得到的Mo P和CoP分别溶解在Cd(NO_3)_2·4H_2O溶液中,在搅拌状态下逐滴加入Na_2S溶液形成沉淀,即可得到复合物磷化物/CdS.CoP/CdS和Mo P/CdS的HRTEM观察显示,磷化物助催化剂与CdS半导体紧密结合,证明了共沉淀法制备助催化剂/半导体复合光催化剂的有效性.磷化物与CdS的紧密结合促进了光激发电子从CdS向磷化物转移,从而大大提高了光催化产氢活性.这项工作为低成本大规模制备光催化剂和光催化产H_2实现工业化提供了一条可行性思路.

Large-scale synthesis of noble-metal-free phosphide/CdS composite photocatalysts for enhanced H2 evolution under visible light irradiation

Photocatalytic H2 evolution under visible light irradiation is an ideal process for solving energy shortage. The low cost of photocatalysts and high efficiency of hydrogen evolution are the two key factors to realize the industrialization of the process. The substitution of a noble-metal cocatalyst with a non-noble-metal catalyst can significantly reduce the cost of the photocatalyst. The large-scale synthesis and assembly of semiconductors and non-noble-metal cocatalysts to form photo-catalysts through a simple method can further decrease the cost of photocatalysis. Here, we report a large-scale and low-cost coprecipitation method to form phosphide/CdS photocatalysts to realize photocatalytic H2evolution. CoP and MoP cocatalysts significantly enhanced the photocatalytic production of hydrogen. The optimal H2 production rates on CoP/CdS and MoP/CdS were 140 and 78 μmol/h, which were 7.0 and 4.0 times higher than those obtained with bare CdS, respectively, and 2.0 times and 1.1 times higher than those obtained with 1.0% Pt/CdS, respectively. This work provides a practical method for the large-scale preparation of low-cost photocatalysts.