催化学报

催化学报 ›› 2027, Vol. 92: 130-144.DOI: 10.1016/S1872-2067(26)65194-7

• 论文 • 上一篇    下一篇

同构共价有机框架局域电子不对称促进电荷分离用于高效光合成H2O2

张养鹏a,1, 吴优a,1, 顾钱锋b,1, 高玥a, 蔡陈枨a, 刘浩宇c, 赵悦含d, 李中华a,*, 张凤鸣e,*, 刘扬c,*, 张其春b,f,*   

  1. a哈尔滨工业大学化工与化学学院, 黑龙江哈尔滨 150001;
    b香港城市大学材料科学与工程学系, 香港 999077;
    c哈尔滨工业大学计算机学院, 黑龙江哈尔滨 150001;
    d香港科技大学(广州)微电子学域, 广东广州 511458;
    e哈尔滨理工大学材料科学与化学工程学院, 黑龙江省二氧化碳资源化利用与能源催化材料重点实验室, 黑龙江哈尔滨 150040;
    f香港城市大学化学系, 超金刚石及先进薄膜研究中心&香港清洁能源研究院, 香港 999077
  • 收稿日期:2026-03-23 接受日期:2026-06-11 出版日期:2027-01-18 发布日期:2026-10-30
  • 通讯作者: *电子信箱: lizh@hit.edu.cn (李中华), zhangfm80@163.com (张凤鸣),liuyang@hit.edu.cn (刘扬), qiczhang@cityu.edu.hk (张其春).
  • 作者简介:1共同第一作者.
  • 基金资助:
    香港城市大学(7020148, 9239116, 9240189, 9380117, 9678403, 9680375, R-IND26401, R-IND26402); 国家自然科学基金(51272052, 62071154); 黑龙江省自然科学基金(LH2019B006).

Engineering local electronic asymmetry in isostructural covalent organic frameworks to maximize charge separation for H2O2 photosynthesis

Yangpeng Zhanga,1, You Wua,1, Qianfeng Gub,1, Yue Gaoa, Chencheng Caia, Haoyu Liuc, Yuehan Zhaod, Zhonghua Lia,*, Feng-Ming Zhange,*, Yang Liuc,*, Qichun Zhangb,f,*   

  1. aSchool of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China;
    bDepartment of Materials Science and Engineering, City University of Hong Kong, Hong Kong SAR 999077, China;
    cSchool of Computer Science and Technology, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China;
    dThrust of Microelectronics, The Hong Kong University of Science and Technology (Guangzhou), Guangzhou 511458, Guangdong, China;
    eHeilongjiang Provincial Key Laboratory of CO2 Resource Utilization and Energy Catalytic Materials, School of Material Science and Chemical Engineering, Harbin University of Science and Technology, Harbin 150040, Heilongjiang, China;
    fDepartment of Chemistry, Center of Super-Diamond and Advanced Films (COSDAF) & Hong Kong Institute of Clean Energy (HKICE), City University of Hong Kong, Hong Kong SAR 999077, China
  • Received:2026-03-23 Accepted:2026-06-11 Online:2027-01-18 Published:2026-10-30
  • Contact: *E-mail: lizh@hit.edu.cn (Z. Li), zhangfm80@163.com (F.-M. Zhang),liuyang@hit.edu.cn (Y. Liu), qiczhang@cityu.edu.hk (Q. Zhang).
  • About author:1 Contributed equally to this work.
  • Supported by:
    City University of Hong Kong (7020148, 9239116, 9240189, 9380117, 9678403, 9680375, R-IND26401, R-IND26402), the National Natural Science Foundation of China (51272052, 62071154), and the Natural Science Foundation of Heilongjiang Province of China (LH2019B006).

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摘要： 以水和空气为原料光催化合成H2O2是替代传统蒽醌法的绿色路径, 具有安全、可按需制备等优势. 然而, H2O2光合成效率长期受限于光生电荷复合以及催化剂结构设计原则不清晰等问题. 共价有机框架(COFs)具有结晶性、多孔性和分子结构可设计性, 是构筑高效光催化体系的重要平台. 现有研究多通过供体-受体结构、缺电子基团或含氮杂环单元调控局域电荷分布, 以促进激子解离, 但往往忽视了COFs骨架的全局对称性对长程电荷传输的影响. 局域电子不对称可增强内建电场, 而高全局对称性有利于形成长程有序的电荷传输通道, 二者之间的协同关系仍缺乏系统性研究. 因此, 阐明COFs骨架的全局对称性与局域电子不对称性对电荷分离和H2O2生成的共同作用, 对于发展高效COFs光催化剂具有重要意义.
本文以1,3,5-三醛基间苯三酚为共同醛单体, 分别引入1,3,5-三氨基苯(TAB)、2,4,6-三氨基嘧啶(TAM)和三聚氰胺(TAT)三种具有不同含氮杂环核心与对称性的胺单体, 构筑了三种同构β-酮烯胺连接的COFs, 即TAB-COF, TAM-COF和TAT-COF, 其整体对称性分别为D3h, C2v和D3h. 实验结果表明, 在可见光照射和O2饱和纯水体系中, TAT-COF的H2O2生成速率达到6497 μmol·g–1·h–1, 分别为TAM-COF和TAB-COF的1.3倍和5.1倍; 当反应介质优化为苄醇后, H2O2生成速率进一步提升至69290 μmol·g–1·h–1, 较纯水体系提高10.7倍, 并优于多数已报道COFs光催化剂. 光物理表征表明, TAT-COF同时具备强光吸收、低电荷转移阻抗和最长载流子寿命, 说明其具有最优的电荷分离与传输能力. 时间相关密度泛函理论计算进一步揭示, TAB-COF虽具有高D3h对称性和多轨道跃迁通道, 但其苯环核心电子分布较对称, 空穴-电子波函数重叠较高, 电荷分离能力有限; TAM-COF因C2v低对称结构产生较强局域极化, 可降低波函数重叠, 但单一主导跃迁通道和较弱光吸收限制了整体性能; TAT-COF则将高D3h骨架对称性与三嗪核心诱导的强局域电子不对称性结合, 既形成有序长程电荷传输网络, 又产生强内建电场以驱动激子快速解离, 其电荷转移优势指数最高(CTAI = 0.043). Hirshfeld电荷、静电势、开路电位、光生电荷密度和电子局域函数分析共同证明, 富氮三嗪核心显著增强了局域极化电子结构. 自由基捕获、原位漫反射红外光谱和电子顺磁共振结果进一步表明, TAT-COF上的H2O2光合成遵循双路径机制: 光生电子参与逐步1e⁻氧还原路径(O2 → •O2– → H2O2), 光生空穴则通过直接2e⁻水氧化路径(2H2O → H2O2 + 2H+)生成H2O2, 从而实现高效原子利用和优异光催化活性.
综上, 本文证明了在同构COFs体系中, 整体骨架对称性与局域电子不对称性的协同优化是提升H2O2光合成效率的关键. 该工作提出了“高整体对称性促进长程传输、强局域电子不对称性促进激子解离”的设计原则, 为高效COFs光催化剂及其他太阳能转化材料的理性构筑提供了重要参考.

关键词: 同构共价有机框架, 局域电子不对称性, 含氮杂环, 过氧化氢生成, 光催化

Abstract: Photosynthesis of H2O2 from water and air offers a sustainable alternative to anthraquinone process. Maximizing photogenerated charge separation is pivotal for high photocatalytic efficiency in covalent organic frameworks, yet a comprehensive understanding of the interplay between global framework symmetry and local electronic asymmetry remains elusive. Herein, three isostructural β-ketoenamine- linked COFs (TAB-COF, TAM-COF, and TAT-COF) were constructed from triamine linkers with distinct N-heterocyclic cores to reveal how the synergy between global framework symmetry and local electronic asymmetry governs charge separation and H2O2 photosynthesis, while yielding frameworks with precisely modulated symmetries (D3h, C2v, and D3h) and electronic properties. TAT-COF, coupling a high-symmetry D3h framework with strongly electron-deficient triazine core, delivered a remarkable rate of 6497 μmol·g–1·h–1 for H2O2 evolution in pure water, further boosted to 69290 μmol·g–1·h–1 in benzyl alcohol, substantially outperforming most reported COF photocatalysts. Time-dependent density functional theory calculations reveal that this exceptional performance originates from the co-optimization of global symmetry, which enables ordered long-range charge transport, and strong local electronic asymmetry, which generates a powerful internal electric field for instantaneous exciton dissociation. Theoretical and in-situ spectroscopic results further associate this optimized charge- separation behavior with a dual-pathway reaction mechanism and the exceptional H2O2 production activity of TAT-COF. This work establishes a concise design principle for advanced photocatalysts: balancing global symmetry with local electronic asymmetry is critical for simultaneously promoting charge separation, dual-pathway reactivity, and high photocatalytic efficiency.

Key words: Isostructural covalent organic frameworks, Local electronic asymmetry, N-Heterocycles, Hydrogen peroxide generation, Photocatalysis