Hefei National Laboratory for Physical Sciences at Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science & Technology of China , Hefei, Anhui 230026, P.R. China.
J Am Chem Soc. 2014 May 14;136(19):6826-9. doi: 10.1021/ja501866r. Epub 2014 May 2.
Finding an ideal model for disclosing the role of oxygen vacancies in photocatalysis remains a huge challenge. Herein, O-vacancies confined in atomically thin sheets is proposed as an excellent platform to study the O-vacancy-photocatalysis relationship. As an example, O-vacancy-rich/-poor 5-atom-thick In2O3 porous sheets are first synthesized via a mesoscopic-assembly fast-heating strategy, taking advantage of an artificial hexagonal mesostructured In-oleate complex. Theoretical/experimental results reveal that the O-vacancies endow 5-atom-thick In2O3 sheets with a new donor level and increased states of density, hence narrowing the band gap from the UV to visible regime and improving the carrier separation efficiency. As expected, the O-vacancy-rich ultrathin In2O3 porous sheets-based photoelectrode exhibits a visible-light photocurrent of 1.73 mA/cm(2), over 2.5 and 15 times larger than that of the O-vacancy-poor ultrathin In2O3 porous sheets- and bulk In2O3-based photoelectrodes.
寻找理想的模型来揭示氧空位在光催化中的作用仍然是一个巨大的挑战。在此，我们提出了将氧空位限制在原子薄片中作为研究氧空位-光催化关系的理想平台。例如，通过介观组装快速加热策略，利用人工六方介孔结构的 In-油酸盐配合物，首次合成了富含/缺乏氧空位的 5 原子厚 In2O3 多孔片。理论/实验结果表明，氧空位赋予 5 原子厚 In2O3 薄片一个新的施主能级和增加的密度状态，从而将带隙从紫外光拓宽到可见光区，并提高载流子分离效率。不出所料，富含氧空位的超薄 In2O3 多孔片基光电电极表现出 1.73 mA/cm2 的可见光光电流，比氧空位较少的超薄 In2O3 多孔片和体相 In2O3 基光电电极分别大 2.5 倍和 15 倍。
