Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, USA.
Nano Lett. 2010 Feb 10;10(2):478-83. doi: 10.1021/nl903217w.
We report the synthesis and photoelectrochemical (PEC) studies of TiO(2) nanoparticles and nanowires simultaneously doped with nitrogen and sensitized with CdSe quantum dots (QDs). These novel nanocomposite structures have been applied successfully as photoanodes for PEC hydrogen generation using Na(2)S and Na(2)SO(3) as sacrificial reagents. We observe significant enhanced photoresponse in these nanocomposites compared to N-doped TiO(2) or CdSe QD sensitized TiO(2). The enhancement is attributed to the synergistic effect of CdSe sensitization and N-doping that facilitate hole transfer/transport from CdSe to TiO(2) through oxygen vacancy states (V(o)) mediated by N-doping. The results demonstrate the importance of designing and manipulating the energy band alignment in composite nanomaterials for fundamentally improving charge separation and transport and thereby PEC properties.
我们报告了氮掺杂和 CdSe 量子点（QD）敏化的 TiO(2) 纳米粒子和纳米线的同时合成和光电化学（PEC）研究。这些新型纳米复合材料结构已成功用作 PEC 制氢的光阳极，使用 Na(2)S 和 Na(2)SO(3) 作为牺牲试剂。与 N 掺杂 TiO(2) 或 CdSe QD 敏化 TiO(2) 相比，我们在这些纳米复合材料中观察到了显著增强的光响应。增强归因于 CdSe 敏化和 N 掺杂的协同效应，该效应通过 N 掺杂介导的氧空位状态 (V(o)) 促进从 CdSe 到 TiO(2) 的空穴转移/传输。结果表明，对于从根本上提高电荷分离和传输并从而提高 PEC 性能，设计和操纵复合纳米材料中的能带排列非常重要。
