In situ gold-loaded titania photonic crystals with enhanced photocatalytic activity
In situ gold-loaded titania photonic crystals with enhanced photocatalytic activity
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DOI：
10.1039/c3ta13878j
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发表时间：
2014-01-01
影响因子：
11.9
通讯作者：
Teng, Jinghua
中科院分区：
文献类型：
--
作者：
Cai, Zhongyu;Xiong, Zhigang;Teng, Jinghua
采用两步法制备了具有光催化活性的三维有序大孔载金二氧化钛光子晶体。首先，将聚苯乙烯（PS）胶体、氯金酸和钛（IV）-双乳酸-双氢氧化铵（TiBALDH）溶胶的混合溶液共组装成PS/TiO 2胶体晶体薄膜。随后煅烧的样品导致PS的去除和转化为无定形TiO 2的纳米晶相。得到的3DOM反型TiO 2蛋白石（i-TiO 2-o）和载金的i-TiO 2-o（i-Au-TiO 2-o）显示出厘米级的长程有序。i-TiO 2-o和i-Au-TiO 2-o的光催化活性分别比纳米TiO 2高2倍和5倍。这种增强的光催化性能可以归因于在纳米TiO 2的吸收边附近的慢光子和化学放大光化学的协同效应。本方法比传统的胶体晶体模板法简单直接得多。特别地，金纳米颗粒可以以可控的尺寸和含量原位负载到反蛋白石结构中。此外，通过该方法制备的i-TiO 2-o和i-Au-TiO 2-o薄膜均显示出高度有序的结构，在大面积上没有覆盖层，这有利于目标污染物的吸附和太阳能的最终利用。
A facile two-step method is developed to fabricate three-dimensional ordered macroporous (3DOM) gold-loaded titania (TiO2) photonic crystals with enhanced photocatalytic activities. Firstly, a mixed solution of polystyrene (PS) colloids, chloroauric acid and titanium(IV)-bis-lactato-bisammonium dihydroxide (TiBALDH) sol was co-assembled into PS/TiO2 colloidal crystal films. Subsequent calcination of the samples led to the removal of PS and transformed amorphous TiO2 into the anatase phase. The resultant 3DOM inverse TiO2 opals (i-TiO2-o) and gold-loaded i-TiO2-o (i-Au-TiO2-o) show centimeter-scale long-range ordering. Photocatalytic characterization of the i-TiO2-o and i-Au-TiO2-o showed activities two-and five-fold higher than nanocrystalline TiO2, respectively. This enhanced photocatalytic performance can be attributed to the synergetic effect of slow photons near the absorption edge of anatase TiO2 nanocrystals and chemically amplified photochemistry. The present method is much more simple and straightforward than conventional colloidal crystal templating methods. In particular, the gold nanoparticles can be in situ loaded into the inverse opal structure with controllable size and content. Furthermore, both i-TiO2-o and i-Au-TiO2-o films fabricated by this method show a highly ordered structure without overlayers in a large area, which facilitates the adsorption of target pollutants and ultimate utilization of solar energy.