Gao Junkuo, Cao Shaowen, Tay Qiuling, Liu Yi, Yu Lingmin, Ye Kaiqi, Mun Peter Choon Sze, Li Yongxin, Rakesh Ganguly, Loo Say Chye Joachim, Chen Zhong, Zhao Yang, Xue Can, Zhang Qichun
School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore.
Sci Rep. 2013;3:1853. doi: 10.1038/srep01853.
From atomic level to understand the cluster-size-dependant behavior of dye-sensitized photocatalysts is very important and helpful to design new photocatalytic materials. Although the relationship between the photocatalytic behaviors and particles' size/shape has been widely investigated by theoretical scientists, the experimental evidences are much less. In this manuscript, we successfully synthesized three new ruthenium dye-sensitized polyoxometalates (POM-n, n relate to different size clusters) with different-sized POM clusters. Under visible-light illumination, all three complexes show the stable O2 evolution with the efficient order POM-3 > POM-2 > POM-1. This cluster-size-dependent catalytic behavior could be explained by the different numbers of M = Ot (terminal oxygen) bonds in each individual cluster because it is well-known that Mo = Ot groups are the catalytically active sites for photooxidation reaction. The proposed mechanism of water oxidation for the dye-sensitized POMs is radical reaction process. This research could open up new perspectives for developing new POM-based WOCs.
从原子层面理解染料敏化光催化剂的团簇尺寸依赖性行为对于设计新型光催化材料非常重要且有帮助。尽管理论科学家已广泛研究了光催化行为与颗粒尺寸/形状之间的关系，但实验证据却少得多。在本论文中，我们成功合成了三种具有不同尺寸多金属氧酸盐团簇的新型钌染料敏化多金属氧酸盐（POM-n，n与不同尺寸团簇相关）。在可见光照射下，所有三种配合物均表现出稳定的析氧反应，其效率顺序为POM-3 > POM-2 > POM-1。这种团簇尺寸依赖性催化行为可以用每个单独团簇中不同数量的M = Ot（端基氧）键来解释，因为众所周知，Mo = Ot基团是光氧化反应的催化活性位点。所提出的染料敏化多金属氧酸盐的水氧化机理是自由基反应过程。该研究可为开发新型基于多金属氧酸盐的析氧催化剂开辟新的视角。
