作者：鎢鉬云商  發布時間：2021-01-28  點擊量：102

   清華大學朱永法團隊報道了通過鎢氧化物中的氧空位引導電子-空穴遷移路徑提高其光催化析氧性能的策略。相關研究成果于2021年1月24日發表在《德國應用化學》。

   水分解的整體效率主要受到緩慢的析氧動力學的限制。因此，開發活性析氧催化劑是十分必要的。

   為此，研究人員設計并合成了一種含氧空位的鎢氧化物光催化析氧催化劑，其析氧速率為683μmol·h^-1·g^-1，高于純WO₃（159μmol·h^-1·g^-1）。隨后通過瞬態吸收光譜研究發現，氧空位能產生電子俘獲態，抑制光生載流子的直接復合。另外，Pt助催化劑可以促進電子俘獲態參與反應，進一步提高光催化性能。

    該研究工作利用飛秒瞬態吸收光譜解釋了無機材料的光催化析氧機理，為高效水分解催化劑的設計提供了新的思路。

附：英文原文

Title: Steering electron‐hole migration pathways using oxygen vacancies in tungsten oxides to enhance their photocatalytic oxygen evolution performance

Author: Zhen Wei, Wenchao Wang, Wenlu Li, Xueqin Bai, Jianfeng Zhao, Edmund C. M. Tse, David Lee Phillips, Yongfa Zhu

Issue&Volume: 24 January 2021

Abstract: Overall water splitting efficiency is mainly restricted by the slow kinetics of oxygen evolution. Therefore, it is essential to develop active oxygen evolution catalysts. In this regard, we designed and synthesized a tungsten oxide catalyst with oxygen vacancies for photocatalytic oxygen evolution, which exhibited a higher oxygen evolution rate of 683 μmol·h  ‐1  ·g  ‐1  than that of pure WO  3  (159 μmol·h  ‐1  ·g  ‐1  ). Subsequent study through transient absorption spectroscopy found that the oxygen vacancies can produce electron trapping states to inhibit the direct recombination of photogenerated carriers. Additionally, a Pt cocatalyst can promote electron trapped states to participate in the reaction to improve the photocatalytic performance further. This work uses femtosecond transient absorption spectroscopy to explain the photocatalytic oxygen evolution mechanism of inorganic materials and provides new insights into the design of high‐efficiency water‐splitting catalysts.

DOI: 10.1002/anie.202016170

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202016170