催化学报 ›› 2025, Vol. 77: 236-249.DOI: 10.1016/S1872-2067(25)64778-4

• 论文 • 上一篇    

双空穴提取策略促进钒酸铋光阳极的光电化学水分解

杨花a,1, 周丁龑彦b,1, 田凯歌a, 孔令江a, 安鹏飞c, 张静c, 纪玉金b, 李有勇b,*(), 闫俊青a,*()   

  1. a陕西师范大学材料科学与工程学院, 先进能源技术陕西工程实验室, 应用表面与胶体化学教育部重点实验室, 陕西西安 710119
    b苏州大学, 江苏省碳基功能材料与器件高技术研究重点实验室, 功能纳米与软物质研究院, 江苏苏州 215123
    c中国科学院高能物理研究所北京同步辐射设备, 北京 100049
  • 收稿日期:2025-04-23 接受日期:2025-06-27 出版日期:2025-10-18 发布日期:2025-10-05
  • 通讯作者: *电子信箱: junqingyan@snnu.edu.cn (闫俊青),yyli@suda.edu.cn (李有勇).
  • 作者简介:1共同第一作者.
  • 基金资助:
    国家重点基础研究发展计划(2022YFA1503101);国家自然科学基金(22072081);陕西省国家科学基础研究计划(2023-JC-JQ-16);中央高校基本科研业务费(GK202401005);陕西师范大学材料科学与工程学院青年科学家行动项目(2023YSIP-MSE-SNNU004)

Dual-hole extraction strategy promotes photoelectrochemical water splitting of bismuth vanadate photoanode

Hua Yanga,1, Dingyanyan Zhoub,1, Kaige Tiana, Lingjiang Konga, Pengfei Anc, Jing Zhangc, Yujin Jib, Youyong Lib,*(), Junqing Yana,*()   

  1. aCollege of CheKey Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education; Shaanxi Engineering Laboratory for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi’an 710119, Shaanxi, China
    bInstitute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou 215123, Jiangsu, China
    cBeijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
  • Received:2025-04-23 Accepted:2025-06-27 Online:2025-10-18 Published:2025-10-05
  • Contact: *E-mail: junqingyan@snnu.edu.cn (J. Yan), yyli@suda.edu.cn (Y. Li).
  • About author:1Contributed equally to this work.
  • Supported by:
    National Key Research Program of China(2022YFA1503101);Natural Science Foundation of China(22072081);National Science Basic Research Plan in Shaanxi Province of China(2023-JC-JQ-16);Fundamental Research Funds for the Central Universities(GK202401005);Young Scientist Initiative Project of School of Materials Science and Engineering at Shaanxi Normal University(2023YSIP-MSE-SNNU004)

摘要:

太阳能作为迄今为止最丰富、可持续的清洁能源, 是替代传统化石燃料的理想能源之一. 太阳能光电催化分解水制氢(PEC)作为一种环境友好的可再生能源技术, 受到广泛关注. 光电催化分解水是通过构建光电化学电池来利用太阳能驱动水分解制取氢气的一项技术. 因此寻找合适的光阳极材料对于实现快速光电化学反应和有效的能量转换至关重要. 钒酸铋是一种n型半导体, 具有合适的带隙、载流子寿命长、化学性质稳定和对可见光响应能力强等优点, 成为最有前途的半导体光阳极材料之一. 但因其存在严重的表面电荷复合、电荷传输差、水氧化动力学迟钝等缺点, 钒酸铋光阳极的光电流密度值仍远低于其理论光电流密度(7.5 mA cm-2). 因此, 改善其固有缺陷, 构建高效稳定的钒酸铋基复合光阳极体系是本文的主要研究思路.

元素掺杂入钒酸铋晶格可以有效地促进载流子分离, 从而实现高效的光电催化水分解. 但目前尚未有人关注元素掺杂引起畸变也能促进光生空穴提取至光阳极表面参与水氧化反应. 本文通过掺杂廉价金属Cs诱导钒酸铋晶格发生畸变, 并在经过掺杂的光阳极(Cs-BiVO4)表面修饰铁酸钴(CoFe2O4)作为高效空穴提取层. 这种结合了晶格畸变调控与界面工程的双重策略展现出卓越的协同效应. 在AM 1.5G标准光照(100 mW cm-2)及1.23 V vs. RHE电压条件下, 新制备的CoFe2O4-Cs-BiVO4光阳极实现了5.66 mA cm-2的光电流密度, 比未修饰的原始钒酸铋光阳极提升了3.9倍. 详细的物理化学表征和密度泛函理论计算表明, Cs掺杂诱导的晶格畸变有效地优化了BiVO4体相内的电荷传输环境, 特别促进了光生空穴从BiVO4体相向表面CoFe2O4层的定向迁移, 从而大幅提升了体相载流子的分离效率. 同时, 表面耦合的铁酸钴层作为高效空穴提取层, 为光生空穴提供了快速转移通道和丰富的反应位点, 显著增强了载流子在光阳极/电解液界面的迁移速率. 二者的协同效应有效促进了光生载流子(尤其是空穴)从钒酸铋体相向析氧反应活性位点的高效、定向迁移, 从而有效抑制了光生电子-空穴对的复合, 显著提升了复合光阳极的PEC水氧化性能.

综上, 通过廉价的铯掺杂和铁酸钴表面改性协同策略成功构建了具有双通道空穴提取的高效CoFe2O4-Cs-BiVO4光阳极, 显著提高了钒酸铋光阳极的光电化学水分解性能, 它揭示了双空穴提取策略在太阳能转换过程中的促进作用, 从而为合理设计光阳极开辟了新的途径.

关键词: 钒酸铋, 光电化学水分解, 晶格畸变, 铁酸钴空穴提取层, 双空穴提取

Abstract:

Elemental doping of BiVO4 crystal lattices effectively enhances carrier separation, thereby facilitating efficient photoelectrochemical water splitting. However, the positive effect of elementally induced lattice distortions on hole extraction has been neglected. Herein, the crystal lattice of BiVO4 is distorted by doping with an inexpensive Cs metal; then, CoFe2O4 is used as an efficient hole-extraction layer to further modify the surface of the doped photoanode. Benefiting from the above design, the newly prepared CoFe2O4-Cs-BiVO4 photoanode achieved a photocurrent density of 5.66 mA cm-2 at 1.23 V vs. a reversible hydrogen electrode, indicating a 3.9-fold improvement in photocurrent density. Detailed physicochemical characterization and density functional theory calculations showed that the lattice distortion induced by Cs doping promoted the directional migration of BiVO4 bulk-phase holes to the CoFe2O4 layer. Additionally, the coupled CoFe2O4 can be used as a hole extraction layer to further enhance the interfacial migration of carriers. The synergistic effect of the two effectively promotes the directional migration of photogenerated carriers from the BiVO4 bulk phase to the active sites of the oxygen evolution reaction, thereby effectively inhibiting carrier recombination. This study revealed the positive effect of the dual-hole extraction strategy on solar energy conversion, thereby opening new avenues for the rational design of photoanodes.

Key words: Bismuth vanadate, Photoelectrochemical water splitting, Lattice distortion, CoFe2O4 hole extraction layer, Dual-hole extraction