State Key Laboratory of Physical Chemistry of Solid Surfaces, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
J Am Chem Soc. 2012 Sep 26;134(38):15720-3. doi: 10.1021/ja307449z. Epub 2012 Sep 10.
TiO(2) nanotube arrays (TNTAs) sensitized by palladium quantum dots (Pd QDs) exhibit highly efficient photoelectrocatalytic hydrogen generation. Vertically oriented TNTAs were prepared by a three-step electrochemical anodization. Subsequently, Pd QDs with uniform size and narrow size distribution were formed on TiO(2) nanotubes by a modified hydrothermal reaction (i.e., yielding nanocomposites of Pd QDs deposited on TNTAs, Pd@TNTAs). By exploiting Pd@TNTA nanocomposites as both photoanode and cathode, a substantially increased photon-to-current conversion efficiency of nearly 100% at λ = 330 nm and a greatly promoted photocatalytic hydrogen production rate of 592 μmol·h(-1)·cm(-2) under 320 mW·cm(-2) irradiation were achieved. The synergy between nanotubular structures of TiO(2) and uniformly dispersed Pd QDs on TiO(2) facilitated the charge transfer of photoinduced electrons from TiO(2) nanotubes to Pd QDs and the high activity of Pd QDs catalytic center, thereby leading to high-efficiency photoelectrocatalytic hydrogen generation.
钯量子点（Pd QDs）敏化的 TiO(2) 纳米管阵列（TNTAs）表现出高效的光电催化制氢性能。通过三步电化学阳极氧化法制备了垂直取向的 TNTAs。随后，通过改进的水热反应在 TiO(2) 纳米管上形成了具有均匀尺寸和窄尺寸分布的 Pd QDs，即形成了 Pd QDs 沉积在 TNTAs 上的纳米复合材料（Pd@TNTAs）。通过利用 Pd@TNTA 纳米复合材料作为光阳极和阴极，在 320 mW·cm(-2) 辐照下，在 λ = 330nm 时实现了近 100%的光子到电流转换效率的显著提高，以及 592 μmol·h(-1)·cm(-2) 的光催化制氢速率的极大提高。TiO(2) 的纳米管状结构和 TiO(2) 上均匀分散的 Pd QDs 之间的协同作用促进了光诱导电子从 TiO(2) 纳米管到 Pd QDs 的电荷转移以及 Pd QDs 催化中心的高活性，从而实现了高效的光电催化制氢。
