催化学报 ›› 2026, Vol. 86: 265-276.DOI: 10.1016/S1872-2067(26)65031-0

• 论文 • 上一篇    下一篇

配体-缺陷协同催化剂局部增强CO2浓度实现高效低浓度CO2电化学还原

刘均炎, 邵涛, 彭珣, 刘升卫*()   

  1. 中山大学环境科学与工程学院, 广东省环境污染控制与修复技术重点实验室, 广东广州, 510006
  • 收稿日期:2025-11-11 接受日期:2025-12-02 出版日期:2026-07-18 发布日期:2026-06-12
  • 通讯作者: *电子信箱: liushw6@mail.sysu.edu.cn (刘升卫).
  • 基金资助:
    国家自然科学基金(51872341);国家自然科学基金(22576241);广东省自然科学基金(2024A1515010505);广东省自然科学基金(2025A1515010004)

Ligand-defect synergistic catalyst for localized CO2 concentration enhancement in electrochemical reduction of low concentration CO2

Junyan Liu, Tao Shao, Xun Peng, Shengwei Liu*()   

  1. School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510006, Guangdong, China
  • Received:2025-11-11 Accepted:2025-12-02 Online:2026-07-18 Published:2026-06-12
  • Contact: *E-mail: liushw6@mail.sysu.edu.cn (S. Liu).
  • Supported by:
    National Natural Science Foundation of China(51872341);National Natural Science Foundation of China(22576241);Natural Science Foundation of Guangdong Province(2024A1515010505);Natural Science Foundation of Guangdong Province(2025A1515010004)

摘要:

利用可再生能源驱动二氧化碳还原反应(CO2RR)以合成高价值化学品, 被认为是实现“碳闭环”的关键技术路径, 对于应对全球能源和环境危机具有重要战略意义. 相较于气态产物, 将CO2还原为甲酸等液相产物, 在常温常压下稳定性更高、储存和运输更便利, 应用价值突出. 为实现这一目标, 各种催化剂已被研究和应用于CO2RR. 其中, 铋基材料因其对*OCHO中间体具有适中的吸附能而对*H吸附能较弱, 被公认为生产甲酸最有前途的催化剂之一. 然而, 在实际应用中, 由于CO2传质限制, 其在低浓度条件下的转化仍面临关键挑战.

本文利用原位电化学还原制备了一种2-氨基对苯二甲酸修饰的铋配位化合物(Re-BiBDC-NH2), 用于低浓度CO2的电化学还原. 具体而言, 原位还原后保留的氨基官能团诱导产生丰富的不饱和配位位点, 增强了CO2吸附能力, 即使在低浓度CO2供给下也能实现局域浓度富集. 更重要的是, 原位电化学重构后残留的表面氨基配体与铋缺陷位点可协同产生动态受阻路易斯酸碱对, 这有助于在低CO2浓度下强化CO2吸附. 在H型电解池中, Re-BiBDC-NH2催化剂在−0.7至−1.4 V(相对于可逆氢电极)的宽电位窗口内保持> 80%的甲酸盐法拉第效率(FEformate), 并在−1.0 V时观察到FEformate最佳性能为96.94%. 该催化剂进一步表现出对不同CO2浓度(15%-100%)和温度(10-50 °C)的耐受性, FEformate均能保持在75%以上. 在电流密度为300 mA cm-2的流动池中, Re-BiBDC-NH2催化剂在不同pH环境(pH = 1.7, 7和14)下FEformate均能实现> 95%. 值得注意的是, 在酸性电解质(pH = 1.7)中, 因可避免碳酸盐产生, 其单程碳效率达到71.60%. 这种配体-缺陷协同作用动态调控了反应界面, 克服了传统催化剂在pH、温度和CO2浓度方面的局限性. 原位光谱分析和密度泛函理论计算表明, 由氨基和缺陷形成的动态受阻路易斯酸碱对能够富集CO2并稳定反应中间体*OCHO, 从而降低反应能垒, 同步提升催化活性与选择性.

综上, 本研究为低浓度CO2RR提供了一种具有配体-缺陷协同效应的催化剂, 为连接催化剂基础研究与实际CO2转化应用提供了新的见解.

关键词: 二氧化碳电化学还原, 铋基催化剂, 甲酸, 受阻路易斯酸碱对, 宽pH值窗口

Abstract:

Electrochemical CO2 reduction reaction (CO2RR) is a potential strategy for mitigating severe greenhouse effect. Despite its potential, CO2RR encounters critical challenges to convert low CO2 concentrations in practical scenarios, due to the CO2 mass transfer limitations. Herein, we prepared a reduced 2-aminoterephthalic acid modified bismuth coordination compound (Re-BiBDC-NH2) for CO2RR in low CO2 concentrations. Retained amino groups after in situ reduction induce abundant unsaturated coordination sites, enhancing CO2 adsorption and enabling localized concentration enhancement even under low CO2 supply concentrations. As such, the optimized Re-BiBDC-NH2 achieves a Faradaic efficiency for formate (FEformate) of > 80% at a wide potential range of 700 mV, FEformate of >75% across 15%-100% CO2 concentrations. Furthermore, in a flow cell at a current density of 300 mA cm-2 and across a wide pH range (pH = 1.7, 7, and 14), the Re-BiBDC-NH2 catalyst achieved FEformate > 95%, with a single-pass carbon efficiency (SPCE) reaching 71.6% in acidic electrolyte (pH = 1.7). In situ spectroscopies and Density functional theory calculations reveal that dynamically frustrated Lewis pairs formed by amino groups and defects concentrate CO2, and stabilize *OCHO intermediates to reduce energy barriers, thereby not only enhancing the CO2RR performance but also allowing reaction to operate under low CO2 concentrations. This work presents a promising ligand-defect synergistic catalyst for low-concentration CO2RR, offering insights for bridging catalyst research and practical CO2 conversion.

Key words: CO2 electrochemical reduction, Bi-based catalysts, Formate, Frustrated Lewis pairs, Wide pH window