Synthesis and characterization of Cu2O/TiO2 photocatalysts for H2 evolution from aqueous solution with different scavengers
Synthesis and characterization of Cu2O/TiO2 photocatalysts for H2 evolution from aqueous solution with different scavengers
复制标题
DOI：
10.1016/j.apsusc.2014.11.027
复制
发表时间：
2015-01-01
影响因子：
6.7
通讯作者：
Hukey, Zongyuan
中科院分区：
文献类型：
--
作者：
Li, Yanping;Wang, Baowei;Hukey, Zongyuan
采用改进的乙醇诱导法制备了一系列不同Cu 2 O摩尔分数的Cu 2 O/TiO 2光催化剂。通过X射线光电子能谱（XPS）表征，证明铜化合物的化学状态为氧化亚铜。采用X射线衍射（XRD）、透射电子显微镜（TEM）、N2吸附-脱附和紫外-可见光谱（UV-vis）等手段对样品的形貌、结构和光学性能进行了表征。结果表明，n型TiO 2与p型Cu 2 O复合后，由于p-n异质结的存在，其光催化活性显著提高。Cu 2 O与TiO 2之间的p-n异质结可以增强可见光吸收，有效抑制电荷复合，促进界面电荷转移，特别是在光催化剂表面提供丰富的反应活性位。因此，制备的2.5-Cu 2 O/TiO 2光催化剂表现出最高的光催化活性为H-2的释放速率，达到2048.25 μ mol/（g h），这是14.48倍，大于纯P25。2.5-Cu 2 O/TiO 2样品在365 nm处的表观量子产率（AQY）估计为4.32%。此外，还讨论了甲醇、无水乙醇、乙二醇和甘油等清除剂对光催化活性的影响。(C)2014爱思唯尔有限公司版权所有。
A series of Cu2O/TiO2 photocatalysts with different molar fraction of Cu2O were prepared by a facile modified ethanol-induced approach followed by a calcination process. The chemical state of copper compound was proved to be cuprous oxide by the characterization of X-ray photoelectron spectra (XPS). Furthermore, these composite oxides were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), N-2 adsorption desorption and UV-vis techniques to study the morphologies, structures, and optical properties of the as-prepared samples. The results indicated that the photocatalytic activity of n-type TiO2 was significantly enhanced by combined with p-type Cu2O, due to the efficient p-n heterojunction. The p-n heterojunction between Cu2O and TiO2 can enhance visible-light adsorption, efficiently suppress charge recombination, improve interfacial charge transfer, and especially provide plentiful reaction active sites on the surface of photocatalyst. As a consequence, the prepared 2.5-Cu2O/TiO2 photocatalyst exhibited the highest photocatalytic activity for H-2 evolution rate and reached 2048.25 mu mol/(g h), which is 14.48 times larger than that of pure P25. The apparent quantum yield (AQY) of the 2.5-Cu2O/TiO2 sample at 365 nm was estimated to be 4.32%. In addition, the influence of different scavengers, namely methanol, anhydrous ethanol, ethylene glycol and glycerol, on the photocatalytic activity for H-2 evolution rate was discussed. (C) 2014 Elsevier B.V. All rights reserved.