Charge separation and catalytic activity of Ag@TiO2 core-shell composite clusters under UV-irradiation
Charge separation and catalytic activity of Ag@TiO2 core-shell composite clusters under UV-irradiation
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DOI：
10.1021/ja042925a
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发表时间：
2005-03-23
影响因子：
15
通讯作者：
Kamat, PV
中科院分区：
文献类型：
--
作者：
Hirakawa, T;Kamat, PV
用稳态和激光脉冲激发法研究了Ag@Ti02复合团簇的光催化性能。Ti02壳层的光激发导致了电子在银芯中的积累，表面等离子激元带从460 nm移动到420 nm。当将电子受体如02、硫醚或C-60引入系统中时，存储的电子被释放。C-60/C-60(.-)等氧化还原电偶的电荷平衡表明，这些核壳结构具有光催化还原反应的能力。讨论了TiO2壳激发后的电荷分离、电荷存储和界面电荷转移步骤。
Photocatalytic properties of Ag@TiO2 composite clusters have been investigated using steady state and laser pulse excitations. Photoexcitation of TiO2 shell results in accumulation of the electrons in the Ag core as evidenced from the shift in the surface plasmon band from 460 to 420 nm. The stored electrons are discharged when an electron acceptor such as 02, thionine, or C-60 is introduced into the system. Charge equilibration with redox couple such as C-60/C-60(.-) shows the ability of these core shell structures to carry out photocatalytic reduction reactions. The charge separation, charge storage, and interfacial charge-transfer steps that follow excitation of the TiO2 shell are discussed.