Abstract：
Plasmonic metal-semiconductor hybrid photocatalysts have received much attention because of their wide light harvesting range and efficient charge carrier generation capability originating from plasmon energy transfer. Here, we introduce a plasmonic metal-semiconductor hybrid nanostructure consisting of a Au core-satellite assembly and crystalline TiO2. The formation of Au@TiO2-Au core-satellite assemblies using TiO2 as a spacer and the subsequent growth of outer TiO2 shells on the core-satellite assemblies, followed by calcination, successfully generated Au core-satellite assembly@TiO2 nanostructures. Exquisite control over the growth of the TiO2 interlayer enabled the regulation of the gap distance between the core and satellite Au nanocrystals within the same hybrid morphology. Due to the structural controllability of the present approach, the gap-distance-dependent plasmonic and photocatalytic properties of the hybrid nanostructures could be explored. The nanostructures possessing the most closely arranged Au nanocrystals showed high photocatalytic activity under visible to near-infrared light irradiation, which can be attributed to strong plasmon coupling between the core and satellite Au nanocrystals that can expedite the formation of intense plasmon energy and its transfer to TiO2.
摘要：
等离子体金属-半导体混合光催化剂由于其宽的光收集范围和源自等离子体能量转移的有效电荷载流子生成能力而受到了很多关注。这里,我们介绍了一种等离子体金属-半导体混合纳米结构，该结构由Au核-卫星组件和晶体TiO2组成。使用TiO2作为间隔物形成Au@TiO2-Au核心-卫星组件，随后在核心-卫星组件上生长TiO2外壳，然后煅烧，成功生成Au核-卫星组装@TiO2纳米结构。对TiO2中间层的生长的精细控制使得能够在相同的混合形态内调节核心和卫星Au纳米晶体之间的间隙距离。由于本方法的结构可控性，可以探索混合纳米结构的间隙距离依赖性等离子体和光催化性能。具有排列最紧密的Au纳米晶体的纳米结构在可见光到近红外光照射下显示出高的光催化活性。这可以归因于核心和卫星Au纳米晶体之间的强等离子体激元耦合，可以加速强烈的等离子体激元能量的形成及其向TiO2的转移。
