广州大学刘兆清团队报道了压缩原子间距离刺激光催化氧偶联到过氧化氢。相关研究成果发表在2024年12月10日出版的国际知名学术期刊《科学通报》。

光催化过氧化氢（H₂O₂）的产生在很大程度上，取决于超氧阴离子自由基（O2⋅−）中间体的缓慢转化动力学，因为中间体的反应性相对较低，需要高能量。

该文中，研究人员提出了一种晶格应变策略，通过优化两个相邻活性位点之间的距离来加速O2⋅−转化为高活性单线态氧（¹O₂），从而通过低势垒氧-氧偶联刺激H₂O₂的产生。

作为初步证明，ZnIn₂S₄纳米片中的缺陷诱导应变将两个相邻Zn位点的距离从3.85优化到3.56，导致具有0.7%压缩应变的ZnIn₂S₄在牺牲剂的作用下，产生3086.00μmol g^-1 h^-1的H₂O₂产量。这种性能归因于压缩的相邻Zn位点之间电子耦合的应变诱导增强，这促进了与活性¹O₂中间体的低势垒氧-氧耦合。

该发现为原子尺度操纵反应位点铺平了道路，为高效的H₂O₂光合作用提供了一种有前景的方法。

附：英文原文

Title: Compressive interatomic distance stimulates photocatalytic oxygen-oxygen coupling to hydrogen peroxide

Author: Zhao-Qing Liu a

Issue&Volume: 2024/12/10

Abstract: Photocatalytic hydrogen peroxide (H2O2) generation is largely subject to the sluggish conversion kinetics of the superoxide radical (O2) intermediate, which has relatively low reactivity and requires high energy. Here, we present a lattice-strain strategy to accelerate the conversion of O2 to highly active singlet oxygen(1O2) by optimizing the distance between two adjacent active sites, thereby stimulating H2O2 generation via low-barrier oxygen-oxygen coupling. As the initial demonstration, the defect-induced strain in ZnIn2S4 nanosheet optimizes the distance of two adjacent Zn sites from 3.85 to 3.56 , resulting in that ZnIn2S4 with 0.7% compressive strain affords 3086.00μmol g-1 h-1 yield of H2O2 with sacrificial agent. This performance is attributed to the strain-induced enhancement of electron coupling between the compressed adjacent Zn sites, which promotes low-barrier oxygen-oxygen coupling to active 1O2 intermediate. This finding paves the way for atomic-scale manipulation of reactive sites, offering a promising approach for efficient H2O2 photosynthesis.

DOI: 10.1016/j.scib.2024.12.014

Source: https://www.sciencedirect.com/science/article/abs/pii/S2095927324009186