Enhanced Photoelectrocatalytic Reduction of Oxygen Using Au@TiO2 Plasmonic Film

详细信息    查看全文

• 作者：Limin Guo ; Kun Liang ; Kyle Marcus ; Zhao Li ; Le Zhou ; Prabhu Doss Mani ; Hao Chen ; Chen Shen ; Yajie Dong ; Lei Zhai ; Kevin R. Coffey ; Nina Orlovskaya ; Yong-Ho Sohn ; Yang Yang
• 刊名：ACS Applied Materials & Interfaces
• 出版年：2016
• 出版时间：December 28, 2016
• 年：2016
• 卷：8
• 期：51
• 页码：34970-34977
• 全文大小：565K
• ISSN：1944-8252

文摘

Novel Au@TiO₂ plasmonic films were fabricated by individually placing Au nanoparticles into TiO₂ nanocavity arrays through a sputtering and dewetting process. These discrete Au nanoparticles in TiO₂ nanocavities showed strong visible-light absorption due to the plasmonic resonance. Photoelectrochemical studies demonstrated that the developed Au@TiO₂ plasmonic films exhibited significantly enhanced catalytic activities toward oxygen reduction reactions with an onset potential of 0.92 V (vs reversible hydrogen electrode), electron transfer number of 3.94, and limiting current density of 5.2 mA cm^–2. A superior ORR activity of 310 mA mg^–1 is achieved using low Au loading mass. The isolated Au nanoparticle size remarkably affected the catalytic activities of Au@TiO₂, and TiO₂ coated with 5 nm Au (Au₅@TiO₂) exhibited the best catalytic function to reduce oxygen. The plasmon-enhanced reductive activity is attributed to the surface plasmonic resonance of isolated Au nanoparticles in TiO₂ nanocavities and suppressed electron recombination. This work provides comprehensive understanding of a novel plasmonic system using isolated noble metals into nanostructured semiconductor films as a potential alternative catalyst for oxygen reduction reaction.