Nano-Au-modified TiO 2 grown on dendritic porous silica particles for enhanced CO 2 photoreduction
Nano-Au-modified TiO 2 grown on dendritic porous silica particles for enhanced CO 2 photoreduction
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DOI：
10.1016/j.micromeso.2020.110635
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发表时间：
2021-01-01
影响因子：
5.2
通讯作者：
Du, Xin
中科院分区：
文献类型：
--
作者：
Wang, Xuan;Xuan, Xiaoni;Du, Xin
在众多的半导体光催化剂中，二氧化钛（TiO 2）具有制备简单、成本低、稳定性高、带隙合适等优点，在光催化还原CO2方面得到了广泛的研究。然而，大多数基于TiO 2的光催化剂的CO2转化效率仍然相对较低，特别是在可见光区域，这是由于它们的弱光吸收能力。在这项工作中，我们采用树枝状多孔二氧化硅纳米球（DPSNs）作为载体的中心径向大孔的表面上生长的TiO 2纳米粒子（NPs），然后负载小Au NPs上的分散良好的TiO 2 NPs。最终，通过控制煅烧时间，成功构建了一系列不同尺寸Au纳米颗粒的DPSNs@TiO2@Au纳米复合材料。由于引入了具有局部表面等离子体共振（LSPR）效应的Au，具有适当尺寸（3-5 nm）的Au NPs的DPSNs@TiO2@Au在300 W白炽灯的模拟阳光照射下表现出上级的CH 4产生速率（34.25 μ molg-TiO 2 @ Au 1h-1）、中等的CO产生速率（15.27 μ molg-TiO 2 @Au-1h-1）和高的循环稳定性。这一工作为负载型光催化剂的设计提供了一定的启示。
Titania dioxide (TiO2) is widely studied for photocatalytic CO2 reduction among various semiconductor pho-tocatalysts due to simple preparation, low cost, high stability and suitable band gap. However, the CO2 conversion efficiency of most TiO2-based photocatalysts is still relatively low, especially in the visible light region owing to their weak light absorption capacity. In this work, we employed dendritic porous silica nanospheres (DPSNs) with center-radial large pores as a carrier to grow TiO2 nanoparticles (NPs) on the surface of center radial pores and then load small Au NPs on the well-dispersed TiO2 NPs. Eventually, a series of DPSNs@TiO2@Au nanocomposites with different sizes of Au NPs were successfully constructed by controlling the calcination time. Due to the introduction of Au with the Local Surface Plasmaon Resonance (LSPR) effect, DPSNs@TiO2@Au with appropriate size (3-5 nm) of Au NPs exhibited superior CH4 production rate of 34.25 mu molg-TiO2@Au1h-1, medium CO production rate of 15.27 mu molg-TiO2@Au-1h-1 and high cycle stability under simulated sunlight irradiation with 300 W Xe lamp. This work may provide some inspiration for the design of the supported photocatalysts.