催化学报 ›› 2026, Vol. 89: 279-291.DOI: 10.1016/S1872-2067(26)65164-9

• 论文 • 上一篇    下一篇

Mo空位与界面Mo-S键修饰的Bi2Mo1-xO6/ZnIn2S4 S型异质结光催化木质素氢解中水活化与质子转移机制

梁姜宇山a, Abdelkader Labidia, 王传义a,b,*()   

  1. a陕西科技大学环境科学与工程学院,陕西西安 710021,中国
    b朱拉隆功大学工程学院环境与可持续工程系,曼谷,泰国
  • 收稿日期:2026-02-15 接受日期:2026-03-26 出版日期:2026-10-18 发布日期:2026-09-01
  • 通讯作者: *电子信箱: wangchuanyi@sust.edu.cn (王传义).
  • 基金资助:
    国家自然科学基金(21976116);国家自然科学基金(52161145409);国家外国专家局专项"一带一路"创新人才交流外国专家项目(2023041004L);高端外国专家项目(G2023041021L);德国亚历山大·冯·洪堡基金会

Unveiling the pathway of water activation and proton transfer in photocatalytic lignin biomass hydrogenolysis over Mo vacancy and Mo-S bond engineered Bi2Mo1-xO6/ZnIn2S4 S-scheme heterojunction

Jiangyushan Lianga, Abdelkader Labidia, Chuanyi Wanga,b,*()   

  1. aSchool of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi’an 710021, Shaanxi, China
    bDepartment of Environmental and Sustainable Engineering, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand
  • Received:2026-02-15 Accepted:2026-03-26 Online:2026-10-18 Published:2026-09-01
  • Contact: *E-mail:wangchuanyi@sust.edu.cn(C. Wang).
  • Supported by:
    National Natural Science Foundation of China(21976116);National Natural Science Foundation of China(52161145409);SAFEA of China “Belt and Road” Innovative Talent Exchange Foreign Expert Project(2023041004L);High-end Foreign Expert Project(G2023041021L);Alexander von Humboldt Foundation(Group-Linkage Program)

摘要:

木质素作为自然界中最丰富的可再生芳香族碳资源, 将其转化为高附加值化学品是替代化石资源、实现绿色可持续发展的重要路径. 然而, 传统的木质素转化方法往往面临反应条件苛刻、效率低下以及依赖有毒溶剂等限制. 近年来, 光催化技术因其条件温和且环境友好而备受关注. 特别是在光催化氢解过程中, 利用丰富且环境友好的水作为质子源, 展现出巨大的应用潜力. 尽管水在一定程度上能够促进木质素关键化学键(如Cβ-O键)的断裂, 但水分子在催化剂表面的微观活化机制以及质子向目标化学键转移的微观路径依然不够明确. 该微观机理认知的缺失, 严重制约了高效光催化体系的合理设计与开发.

为了突破上述瓶颈, 本文提出了一种协同缺陷与界面工程的设计思路, 通过简便的原位溶剂热法, 成功构建了富含Mo空位的S型Bi2Mo1-xO6/ZnIn2S4异质结光催化剂. 该设计旨在建立原子级的Mo-S界面键, 并利用水作为唯一质子源实现木质素Cβ-O键的选择性氢解. 实验表征与密度泛函理论(DFT)计算结果表明, 引入的Mo空位在体系中发挥了双重关键作用: 一方面, 它诱导了界面Mo-S键的形成, 构建了高效的原子级电荷转移通道, 保障了光生载流子遵循S型电荷转移机制进行空间定向分离, 从而保留了具有强氧化还原能力的电子和空穴; 另一方面, Mo空位驱动了空穴在缺陷位点的局域化, 极大地促进了水分子的解离, 为后续木质素氢解反应提供了充足的活性质子. 在反应机理与性能评估方面, 本文以2-苯氧基-1-苯基乙醇(PP-ol)为木质素模型化合物进行了系统研究. 在可见光照射(λ > 420 nm)和空气氛围下, 该催化剂对PP-ol的转化率超过90%, 表观量子产率达到5.71%, 优于目前文献报道的大多数光催化剂. 原位电子顺磁共振和原位X-射线光电子能谱分析证实了S型异质结的内建电场驱动机制以及活性氧物种对木质素底物的有效活化. 更重要的是, 通过同位素标记实验(使用D2O和CD3CN)结合液相色谱-质谱分析, 在原子-分子水平上证实了水解离产生的质子是木质素氢解反应的直接氢源. 动力学同位素效应实验进一步证明了水分子O-H键的断裂是该过程的决速步. DFT计算进一步从热力学和动力学层面阐明, Mo空位的引入显著降低了水解离的活化能垒(从0.756 eV降至0.598 eV), 从而加速了质子的生成与转移.

综上, 本文通过S型异质结中Mo空位与界面键合的协同工程, 构建了高效选择性转化木质素的S型Bi2Mo1-xO6/ZnIn2S4异质结光催化体系. 结合原位分析与同位素示踪等, 深入揭示了光催化木质素转化中水驱动的质子转移微观机制. 这不仅为从原子分子尺度解析光催化水活化机制提供全新理论依据, 也为设计利用绿色质子源高效转化生物质的新型光催化材料提供了重要的科学指导与技术参考.

关键词: 光催化氢解, Mo空位, 水活化, S型异质结, 质子转移

Abstract:

Utilizing water as a green and abundant proton source for the photocatalytic hydrogenolysis of lignin under mild conditions represents a promising approach for biomass conversion. However, the microscopic mechanism of water activation and subsequent proton transfer remains unclear, hindering the rational design of efficient catalytic system. Herein, Mo vacancy-engineered S-scheme Bi2Mo1-xO6/ZnIn2S4 heterojunction was constructed via a facile in-situ solvothermal process. Combining density functional theory calculations, in-situ electron paramagnetic resonance and X-ray photoelectron spectroscopy analyses reveal that the presented Mo vacancies play a dual role; they not only induce the formation of interfacial Mo-S bonds, creating atomic-level charge-transfer channels, but also drive hole localization, promoting water dissociation and generating protons for the selective hydrogenolysis of lignin Cβ-O bonds. Crucially, isotope labeling experiments directly confirm that the protons generated from water dissociation serve as the direct hydrogen source for the lignin hydrogenolysis reaction. Under visible light exposure (λ > 420 nm) and an air atmosphere, the developed catalyst achieves over 90% photoconversion of 2-phenoxy-1-phenylethanol (PP-ol) lignin with a quantum yield of 5.71%, outperforming the most reported photocatalysts. Through synergistic engineering of Mo vacancies and interfacial bonds in S-scheme heterojunctions, this study provides key insights into the water-driven proton transfer mechanism in photocatalytic hydrogenolysis of lignin, highlighting an efficient biomass photoconversion strategy.

Key words: Photocatalytic hydrogenolysis, Mo vacancies, Water activation, S-Scheme heterojunction, Proton transfer