[2008年05月28日]

 

我组继在光催化剂表面异相结及其光催化性能的研究工作Angew. Chem. Int. Ed.(张静、李灿等,2008DOI: 0.1002/anie.200704788)取得重要进展的基础上,最近又在表面异质结光催化剂制备及其光催化制氢研究中取得重要进展,研究结果发表在J. Am. Chem. Soc.(宗旭、李灿等,2008DOI: 10.1021/ja8007825),美国C&E NEWS就这一研究进展在Science & Technology Concentrates栏目中给予Highlight

光催化剂的设计合成是发展太阳能催化制氢的关键,而发展高而效廉价的实用光催化剂面临巨大的挑战。这项工作借鉴半导体异质结概念在纳米CdS表面上组装纳米MoS2,使CdSMoS2在原子层次上形成异质结,使光生电子和空穴的分离效率大幅度提高,从而获得高活性光催化剂。在这项研究中发现MoS2/CdS的光催化产氢活性比单独的CdS催化剂高30倍以上,在相同的实验条件下MoS2/CdS比担载贵金属助剂PtRuRhPdAuCdS的光催化产氢活性还要高。该工作不仅表明表面异质结的形成可促进光生电子-空穴的分离,显著提高光催化活性,而且还发现在光催化剂中用相对廉价的MoS2代替贵金属助催化剂的可能性。这项工作对发展太阳能高效光催化剂及其光催化制氢过程具有重要指导意义和潜在的应用价值。

Abstract: This communication presents our recent results that the activity of photocatalytic H2 production can be significantly enhanced when small amount of MoS2 is loaded on CdS as co-catalyst. The MoS2/CdS catalysts show high rate of H2 evolution from photocatalytic reforming of lactic acid under visible light irradiation. The rate of H2 evolution on CdS is increased by up to 36 times when loaded with only 0.2 wt% of MoS2, and the activity of MoS2/CdS is even higher than those of the CdS photocatalysts loaded with different noble metals, such as Pt, Ru, Rh, Pd and Au. The junction formed between MoS2 and CdS and the excellent H2 activation property of MoS2 are supposed to be responsible for the enhanced photocatalytic activity of MoS2/CdS.

Keywordsphotocatalyst • hydrogen • MoS2 • heterogeneous junction