Synthesis and Ag-loading-density-dependent photocatalytic activity of Ag@TiO2 hybrid nanocrystals
Synthesis and Ag-loading-density-dependent photocatalytic activity of Ag@TiO2 hybrid nanocrystals
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Ag@TiO2杂化纳米晶的合成及其载银密度依赖性光催化活性
DOI：
10.1016/j.apsusc.2013.08.051
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发表时间：
2013-11-01
影响因子：
6.7
通讯作者：
Shao, Guosheng
中科院分区：
文献类型：
--
作者：
Chen, Deliang;Chen, Qianqian;Shao, Guosheng
在TiO2 （P25）纳米粒子存在的条件下，在eg -乙醇溶液中光还原Ag+，合成了银修饰的TiO2纳米粒子（Ag@TiO2）。透射电镜观察表明，粒径在1 ~ 3 nm范围内的银纳米团簇（nc）均匀地固定在TiO2纳米颗粒表面。通过改变其前驱体中Ag+的浓度，合成了含有不同数量Ag nc（质量为0.5-10%）的Ag@TiO2纳米复合材料。在可见光照射下（λ >= 400 nm），对合成的Ag@TiO2纳米复合材料的光催化活性进行了研究。结果表明：Ag@TiO2纳米复合材料具有新型的Ag负载密度依赖性光催化活性，且在相同条件下，与1% Ag纳米结构相似的Ag@TiO2光催化剂具有较高的光催化速率常数，比P25 TiO2的光催化速率常数高22倍。Ag纳米碳纳米管的LSPR特性增强了其光催化性能。详细讨论了银负载-密度依赖性光催化性能的可能机理。(C) 2013 Elsevier b.v.版权所有
Silver-decorated TiO2 nanoparticles (Ag@TiO2) were synthesized by photoreducing Ag+ species in an EG-ethanol solution in the presence of TiO2 (P25) nanoparticles. The TEM observations indicate that the Ag nanoclusters (NCs) with a size range of 1-3 nm were uniformly anchored on the surfaces of TiO2 nanoparticles. The Ag@TiO2 nanocomposites with various amounts of Ag NCs (0.5-10% in mass) were synthesized by changing the concentrations of Ag+ in their precursors. The photocatalytic activity of the as-synthesized Ag@TiO2 nanocomposites was investigated by photodegradating RhB dye under visible-light irradiation (lambda >= 400 nm). The results show that the as-obtained Ag@TiO2 nanocomposites show a novel Ag-loading-density-dependent photocatalytic activity, and that the Ag@TiO2 photocatalyst with similar to 1% Ag NCs has the best photocatalytic performance with a high rate constant, 22 times higher than that of P25 TiO2 under the same condition. The enhanced photocatalytic performance should be attributed to the LSPR property of Ag NCs. The possible mechanism for the Ag-loading-density-dependent photocatalytic performance was discussed in detail. (C) 2013 Elsevier B. V. All rights reserved.