催化学报 ›› 2026, Vol. 80: 113-122.DOI: 10.1016/S1872-2067(25)64883-2

• 论文 • 上一篇    下一篇

β-酮烯胺共价键桥接的S型异质结实现同步光还原CO2为CO以及茴香醇选择性氧化为茴香醛

蒋浩朋a, 李金河a, 于晓慧a,*(), 董慧龙b, 王伟康a,c, 刘芹芹a,*()   

  1. a江苏大学材料科学与工程学院, 江苏镇江 212013
    b苏州工学院材料工程学院, 江苏常熟 215500
    c安徽师范大学化学与材料科学学院, 安徽芜湖 241002
  • 收稿日期:2025-06-05 接受日期:2025-07-06 出版日期:2026-01-18 发布日期:2026-01-05
  • 通讯作者: 于晓慧,刘芹芹
  • 基金资助:
    国家自然科学基金(22472069);国家自然科学基金(22302080);中国博士后科学基金(2024M760028)

Interface engineering of covalent β-ketoenamine-bridged S-scheme heterojunction for synergistic solar-powered CO2-to-CO conversion paired with selective alcohol oxidation

Haopeng Jianga, Jinhe Lia, Xiaohui Yua,*(), Huilong Dongb, Weikang Wanga,c, Qinqin Liua,*()   

  1. aSchool of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China
    bSchool of Materials Engineering, Suzhou University of Technology, Changshu 215500, Jiangsu, China
    cSchool of Chemistry and Materials Science, Engineering Research Center of Carbon Neutrality, Anhui Normal University, Wuhu 241002, Anhui, China
  • Received:2025-06-05 Accepted:2025-07-06 Online:2026-01-18 Published:2026-01-05
  • Contact: Xiaohui Yu, Qinqin Liu
  • Supported by:
    Natural Science Foundation of China(22472069);Natural Science Foundation of China(22302080);China Postdoctoral Science Foundation(2024M760028)

摘要:

光催化还原CO2技术兼具削减人为碳排放与转化太阳能为化学能的双重优势, 是实现碳中和目标的有效路径. 传统体系依赖还原位点多电子转移活化CO2生成碳基化合物, 同时通过水氧化析氧反应(OER)消耗空穴, 但该机制存在固有缺陷: (1) OER的高热力学能垒(>1.23 eV)造成显著能量损失; (2)载流子快速复合导致量子效率衰减. 牺牲剂虽可提升表观活性, 却伴随成本激增与二次污染风险. 因此, 开发同步驱动CO2还原与有机底物选择性氧化的电子-空穴协同利用体系成为突破瓶颈的核心策略.

构建高效的光还原氧化系统需要强大的氧化还原电位、优异的载流子分离动力学以及丰富的活性位点. 本研究通过原位生长技术构建β-酮烯胺共价桥连的Zr-BTB-COF S型异质结, Zr-BTB-NH2的-NH2基团对酮羰基亲核攻击形成烯醇-亚胺中间体, 经1,3-质子转移不可逆异构化为稳定β-酮烯胺键, 实现TpTt-COF在Zr-BTB-NH2表面的原位生长. 透射电子显微镜证实TpTt-COF在载体表面形成紧密界面. X射线光电子能谱技术、原位X射线光电子能谱技术结合紫外-可见漫反射光谱揭示了典型的S型电荷转移路径. 瞬态表面光电压显示内建电场强度提升至纯相的9.8倍. 电化学阻抗实验证实构建界面β-酮烯胺键能够降低电荷转移电阻. 电化学线性扫描伏安法测试结果表明, Zr-BTB-COF-3 (TpTt-COF的含量为10 wt%)复合光催化剂的阴极电流密度是纯Zr-BTB-NH2样品的2.7倍(-2.4 V, 相对于Ag/AgCl). 原位傅里叶变换红外光谱在Zr-BTB-COF-3光催化CO2还原过程中检测到关键中间体*COOH的特征振动峰(1712, cm-¹), 结合在线质谱分析证实其反应遵循CO2 → CO2* → COOH* → CO* → CO(g)路径. 密度泛函理论计算表明, Zr-BTB-COF的CO2物理吸附能提升至0.278 eV (相比纯Zr-BTB-NH2提高了3.3倍), 且速率决定步骤COOH → *CO的自由能垒降至0.88 eV (显著低于Zr-BTB-NH2的1.53 eV), 与动力学实验趋势一致. 通过优化TpTt-COF负载比例, Zr-BTB-COF-3实现CO2还原-茴香醇氧化的双功能协同催化, 获得71.9 μmol·g-1·h-1的CO产率(选择性> 99%)与44.7 μmol·g-1·h-1的茴香醛产率(转化率98.2%).

综上, 本文通过构建β-酮烯胺电子桥介导的S型异质结, 同步提升界面电荷分离效率与氧化还原能力, 为太阳能驱动C-C偶联与C-H氧化协同体系提供了普适性设计策略.

关键词: S型异质结, 共价β-酮烯胺键桥梁, 光催化CO2还原

Abstract:

To address persistent challenge of charge recombination in semiconductor photocatalysis, we engineered an S-scheme heterojunction via covalent β-ketoenamine bridges between zirconium-based MOFs and triazine-COFs (Zr-BTB-COF). This dual-functional system pioneered a "one-photon, two-value" strategy for simultaneous CO2-to-CO reduction and 4-methoxybenzyl alcohol-to-anisaldehyde oxidation, enabling solar-driven carbon refineries. Synergistic in-situ XPS analysis and density functional theory calculations unambiguously validated the S-scheme charge transfer mechanism. The covalent interface overcame lattice mismatch constraints while Fermi-level alignment generated an enhanced built-in electric field (9.8 times stronger than pristine Zr-BTB-NH2), achieving ultrafast charge separation. Low-energy carrier recombination through the β-ketoenamine bridge preserved high-potential carriers (-1.61 V for CO2 reduction; +2.22 V for alcohol oxidation). Critically, this architecture reduced the activation energy barrier for the rate-limiting *COOH → *CO step to ΔG = 0.65 eV, a 42% reduction versus isolated Zr-BTB-NH2. Through concerted thermodynamic and kinetic optimization, the covalent Zr-BTB-COF achieved high CO and anisaldehyde yields (71.9 and 44.7 μmol·g-1·h-1) with internal quantum efficiency of 3.75% (365 nm). This bond-resolved interface engineering paradigm establishes a new design framework for synchronizing carbon-neutral cycles with high-value chemical synthesis.

Key words: S-scheme heterojunction, Covalent β-ketoenamine bridge, Photocatalytic CO2 reduction