Elucidating the Microenvironment Structure‐Activity Relationship of Cu Single‐Site Catalysts via Unsaturated N,O‐Coordination for Singlet Oxygen Production

• Published in: Advanced functional materials 2024-10, Vol.34 (44), p.n/a
• Main Authors: Li, Pengfei, Deng, Yang, Wang, Haiyuan, Luo, Yali, Che, Yin, Bian, Ruijuan, Gao, Ruoyun, Wu, Xianfeng, Zhang, Zhen, Wu, Xu
• Format: Article
• Language: English
• Subjects: Catalysts; Charge transfer; Configurations; Coordination; coordination microenvironment; electron configuration; Oxygen production; Photocatalysis; Photocatalysts; Singlet oxygen; singlet oxygen generation; single‐site catalysts; water treatment
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202407147

Understanding the microenvironment structure‐activity relationship of singlet‐atom catalysts (SACs) is imperative for the development of high‐performance photocatalytic devices. However, the challenge remains to finely regulate the coordination microenvironment of SACs. Herein, single‐atom Nx─Cu─O4‐x (x = 1–4) photocatalysts with different coordination environments are successfully prepared based on pre‐design reticular supramolecular covalent organic frameworks (COFs) for direct photocatalytic 1O2 production from O2. The results show that the high activity of Cu SACs is closely related to the N,O‐coordination microenvironment, which is primarily ascribed to the different electrophilicity of the N, O atom. The electron configuration of N3‐Cu‐O1 endows photocatalyst enhanced charge transfer capability and the nearest D‐band center to the Fermi level. The “end‐on” type adsorption configuration of O2 at the N3─Cu─O1 active site can promote the breaking of Cu─O bonds rather than O─O bonds. As a result, the N3‐Cu‐O1@COF photocatalyst exhibits the most optimal formation and desorption energies for intermediates •OOH, which provides an advantageous reaction pathway with fewer steps and a lower barrier for 1O2 production. This work highlights the structure‐activity relationship of SACs for long‐term applications. Single‐atom Nx‐Cu─O4‐x@COF (x = 1–4) photocatalysts with different coordination environments are prepared based on pre‐design reticular supramolecular COFs for direct photocatalytic 1O2 production from O2. The results indicate that the N3─Cu─O1@COF photocatalyst exhibits superior photoelectric properties and 1O2 generation ability. This work reveals the microenvironment structure‐activity relationship of single‐atom catalysts via finely unsaturated N,O‐coordination.