Shi Xian, Dong Xing'an, Sun Yanjuan, Zhang Shihan, Dong Fan
Research Center for Environmental and Energy Catalysis, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China.
School of Resources and Environment, University of Electronic Science and Technology of China, Chengdu 611731, China.
Research (Wash D C). 2022 Oct 12;2022:9818792. doi: 10.34133/2022/9818792. eCollection 2022.
Surface defects with abundant localized electrons on bismuth oxyhalide catalysts are proved to have the capability to capture and activate CO. However, bismuth oxyhalide materials are susceptible to photocorrosion, making the surface defects easily deactivated and therefore losing their function as active sites. Construction of deactivation-resistant surface defects on catalyst is essential for stable CO photoreduction, but is a universal challenge. In this work, the BiOI nanotubes with surface tensile strain are synthesized, which are favorable for the visible light-induced dynamic I defects generation. The CO molecules absorbed on I defects are constantly reduced by the incoming photogenerated electrons from I-deficient BiOI nanotubes and the successive protonation of CO molecules is thus highly promoted, realizing the selective CO conversion process via the route of CO-COOH-CO. The efficient and stable photoreduction of CO into CO with 100% selectivity can be achieved even under visible light ( >420 nm) irradiation benefited from the dynamic I defects as active sites. The results presented herein demonstrate the unique action mechanism of light-induced dynamic defects during CO photoreduction process and provide a new strategy into rational design of deactivation-resistant catalysts for selective CO photoreduction.
卤氧化铋催化剂上具有大量局域电子的表面缺陷被证明具有捕获和活化CO的能力。然而，卤氧化铋材料易受光腐蚀影响，使得表面缺陷容易失活，从而失去其作为活性位点的功能。在催化剂上构建抗失活的表面缺陷对于稳定的CO光还原至关重要，但这是一个普遍的挑战。在这项工作中，合成了具有表面拉伸应变的BiOI纳米管，这有利于可见光诱导的动态I缺陷的产生。吸附在I缺陷上的CO分子不断被来自缺I的BiOI纳米管的入射光生电子还原，从而极大地促进了CO分子的连续质子化，实现了通过CO-COOH-CO途径的选择性CO转化过程。即使在可见光（>420 nm）照射下，得益于作为活性位点的动态I缺陷，也能实现将CO高效稳定地光还原为CO，选择性达100%。本文给出的结果证明了光诱导动态缺陷在CO光还原过程中的独特作用机制，并为合理设计用于选择性CO光还原的抗失活催化剂提供了新策略。
