文献类型：期刊文献

英文题名：Enhanced photoelectrochemical properties and photocatalytic activity of porous TiO2 films with highly dispersed small Au nanoparticles

作者：Fu, Pingfeng[1,2]; Zhang, Pengyi[1]

第一作者：Fu, Pingfeng

通讯作者：Zhang, P.

机构：[1] State Key Joint Laboratory of Environmental Simulation and Pollution Control, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China; [2] College of Arts and Science, Beijing Union University, Beijing 100083, China

第一机构：State Key Joint Laboratory of Environmental Simulation and Pollution Control, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China

通讯机构：[1]State Key Joint Laboratory of Environmental Simulation and Pollution Control, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China

年份：2011

卷号：519

期号：11

起止页码：3480-3486

外文期刊名：Thin Solid Films

收录：EI(收录号：20111213767487);Scopus(收录号：2-s2.0-79952738097)

语种：英文

外文关键词：Electrolytes - High resolution transmission electron microscopy - Charge transfer - Electrochemical electrodes - Gold deposits - Photocatalysis - Separation - Gold nanoparticles - Electrochemical impedance spectroscopy - Hydrogen bonds - Self assembly - Dispersions - Titanium dioxide

摘要：Small Au nanoparticles (NPs) with mean diameter of 4.1 nm were highly deposited on TiO2 films via a simple electrostatic self-assembly method. The physically separated Au NPs, with a high surface density of 6.3 × 1011 NPs/cm2, were mainly distributed on the top layer of porous TiO2 films. The deposition of Au NPs induced a negative shift (～ 100 mV) of the apparent flat band potential of Au-TiO 2 electrodes. The charge separation efficiency of the TiO2 electrode increased from 72.1% to 88.5% by dispersing Au NPs. Whatever redox species were present in the electrolyte, the Au-TiO2 electrode had higher photovoltage than the TiO2 electrode. The photovoltage was very sensitive to added redox species such as O2, O3, and methanol, and the effect of adsorbed redox species on electron accumulation was discussed. The electrochemical impedance spectroscopic measurements revealed that the charge transfer resistance (Rct) of Au-TiO2 films was reduced to 16% of bare TiO2 electrode, and the decreased R ct corresponded to the increased photocatalytic activity of Au-TiO2 films. The beneficial role of uniformly dispersed small Au NPs on the charge separation was discussed. By modifying TiO2 films with small Au NPs, the photocatalytic activity of TiO2 films for formaldehyde degradation increased about 2.5 times. ? 2011 Elsevier B.V. All rights reserved.