Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
Nanoscale. 2018 Dec 21;10(47):22180-22188. doi: 10.1039/c8nr05144e. Epub 2018 Nov 28.
The use of hot carriers generated from the decay of localized surface plasmon resonance in noble metal nanoparticles is a promising concept for photocatalysis. Here, we report the enhancement of photocatalytic activity by the flow of hot electrons on TiO nanotube arrays decorated with 5-30 nm Au nanoparticles as photoanodes for photoelectrochemical water splitting. This enhanced photocatalytic activity is correlated to the size of the Au nanoparticles, where higher oxygen evolution was observed on the smaller nanoparticles. Conductive atomic force microscopy and ultraviolet photoelectron spectroscopy were used to characterize the Schottky barrier between Au and TiO, which reveals a reduction in the Schottky barrier with the smaller Au nanoparticles and produces an enhanced transfer of photoinduced hot carriers. This study confirms that the higher photocatalytic activity was indeed driven by the hot electron flux generated from the decay of localized surface plasmon resonance.
利用贵金属纳米粒子中局域表面等离激元衰变产生的热载流子是一种很有前途的光催化概念。在这里，我们报告了在 TiO 纳米管阵列上修饰 5-30nm Au 纳米粒子作为光电化学水分解的光阳极，通过热电子流动增强光催化活性。这种增强的光催化活性与 Au 纳米粒子的尺寸有关，其中在较小的纳米粒子上观察到更高的氧气演化。使用导电原子力显微镜和紫外光电子能谱对 Au 和 TiO 之间的肖特基势垒进行了表征，结果表明肖特基势垒随 Au 纳米粒子的减小而减小，从而增强了光诱导热载流子的转移。本研究证实，较高的光催化活性确实是由局域表面等离激元共振衰变产生的热电子流驱动的。
