Enhanced Photocatalytic Activity and Selectivity for CO2 Reduction over a TiO2 Nanofibre Mat Using Ag and MgO as Bi-Cocatalyst
Enhanced Photocatalytic Activity and Selectivity for CO2 Reduction over a TiO2 Nanofibre Mat Using Ag and MgO as Bi-Cocatalyst
复制标题
使用 Ag 和 MgO 作为双助催化剂增强 TiO2 纳米纤维垫的光催化活性和 CO2 还原选择性
DOI：
10.1002/cctc.201801282
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发表时间：
2019
期刊：
影响因子：
4.5
通讯作者：
Ho Wingkei
中科院分区：
文献类型：
--
作者：
Xu Feiyan;Meng Kai;Cheng Bei;Yu Jiaguo;Ho Wingkei
设计和制备新型光催化剂，提高光催化还原CO2的活性和选择性，具有重要的理论和实际意义。在此，我们开发了静电纺丝和湿浸渍方法，以获得Ag和MgO共改性的TiO 2纳米纤维垫。Ag纳米粒子作为电子陷阱，可有效分离TiO 2纳米纤维中的电子-空穴对，并通过形成肖特基势垒减少其复合。光生电子在银纳米颗粒中的积累可以增强CH 4的形成。由于Ag纳米粒子的表面等离子体共振效应，所得到的Ag−MgO− TiO 2复合材料毡表现出更强的可见光吸收。MgO纳米颗粒作为碱性位的沉积有利于CO2分子的吸附。Ag和MgO作为双助催化剂的协同效应有助于提高光催化活性和CO2还原的CH 4-选择性。同位素（13 C）示踪实验证实，该产品是从光催化还原的CO2源，而不是有机污染物。该报告强调了Ag和MgO纳米颗粒的协同效应对增强TiO 2基材料的光催化活性和选择性的重要性。
The design and preparation of novel photocatalysts to enhance photocatalytic activity and selectivity for CO2reduction is highly important both theoretically and practically. Herein, we develop an electrospinning and wet‐impregnation method to obtain an Ag and MgO co‐modified TiO2nanofibrous mat. Ag nanoparticles (NPs) as electron traps can effectively separate electron−hole pairs and reduce their recombination in TiO2nanofibres due to the formation of Schottky barriers. Accumulation of photogenerated electrons in the Ag NPs can enhance the formation of CH4. The obtained Ag−MgO−TiO2composite mat exhibits extended visible light absorption owing to the surface plasmon resonance effect of the Ag NPs. Deposition of MgO NPs, as basic sites, could facilitate the adsorption of CO2molecules. The synergetic effects of Ag and MgO as a bi‐cocatalyst contribute to enhanced photocatalytic activity and CH4‐selectivity for CO2reduction. Isotope (13C) tracer experiments confirm that the products are produced from photocatalytic reduction of the CO2source instead of organic contaminants. This report highlights the importance of the synergistic effect of Ag and MgO NPs on enhancing the photocatalytic activity and selectivity of TiO2‐based materials.