Kobayashi Hisayoshi, Teranishi Miwako, Negishi Ryo, Naya Shin-Ichi, Tada Hiroaki
Department of Chemistry and Materials Technology, Kyoto Institute of Technology , Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan.
Environmental Research Laboratory, Kindai University , 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan.
J Phys Chem Lett. 2016 Dec 15;7(24):5002-5007. doi: 10.1021/acs.jpclett.6b02026. Epub 2016 Nov 28.
Au and Pt nanoparticles with varying mean particle size and comparable loading amounts were loaded on the surface of TiO (Au/TiO and Pt/TiO, respectively). The photocatalytic activities of Au/TiO and Pt/TiO for the oxygen reduction reaction (ORR) in an aerated aqueous solution containing 4% ethanol were compared under ultraviolet-light irradiation at 298 K. The initial rate of HO generation (or HO formation rate) in the Au/TiO system is much greater than that in the Pt/TiO system regardless of the metal particle size. To clarify the origin for the striking difference in the activity, the photocatalytic ORR on the model slabs (M/(TiO) and M/(TiO), M = Au and Pt) was simulated by density functional theory (DFT) calculations taking the solvation effect into consideration. The DFT calculations clearly show that regardless of the cluster size, HO formation more easily occurs structurally and energetically for the Au/TiO system, whereas HO is generated with the O-O bond cleavage in the Pt/TiO system.
将平均粒径不同但负载量相当的金纳米颗粒和铂纳米颗粒分别负载在TiO表面（分别为Au/TiO和Pt/TiO）。在298K的紫外光照射下，比较了Au/TiO和Pt/TiO在含有4%乙醇的曝气水溶液中对氧还原反应（ORR）的光催化活性。无论金属颗粒大小如何，Au/TiO体系中HO的初始生成速率（或HO形成速率）都远大于Pt/TiO体系。为了阐明活性显著差异的根源，考虑溶剂化效应，通过密度泛函理论（DFT）计算模拟了模型平板（M/(TiO)和M/(TiO)，M = Au和Pt）上的光催化ORR。DFT计算清楚地表明，无论团簇大小如何，对于Au/TiO体系，HO在结构和能量上更容易生成，而在Pt/TiO体系中，HO是通过O - O键断裂生成的。
