催化学报 ›› 2026, Vol. 85: 247-257.DOI: 10.1016/S1872-2067(26)65038-3

• 论文 • 上一篇    下一篇

物种异质性调控促进电催化硝酸盐高效还原合成氨

张可阜a,1, 张璐霄a,1, 褚建意a, 梅岑瑜a, 刘思源a, 樊桂兰a, 刘粉荣a, Youngkook Kwonb(), 白凤华a(), 罗文豪a()   

  1. a 内蒙古大学化学化工学院, 内蒙古自治区稀土催化重点实验室, 内蒙古呼和浩特 010020, 中国
    b 蔚山科学技术院能源与化学工程学院&碳中和研究院, 蔚山 44919, 韩国
  • 收稿日期:2025-10-29 接受日期:2025-12-29 出版日期:2026-06-18 发布日期:2026-05-18
  • 通讯作者: *电子信箱: ykwon@unist.ac.kr (Youngkook Kwon),
    f.h.bai@imu.edu.cn (白凤华),
    w.luo@imu.edu.cn (罗文豪).
  • 作者简介:

    1共同第一作者.

  • 基金资助:
    国家自然科学基金(22479082);国家自然科学基金(22562020);内蒙古大学基金(10000-23112101/081);内蒙古青年科技英才基金(NJYT24019);中央引导地方科技发展专项资金(2024ZY0116);广东省重点领域研发项目(2023B0202010027);韩国国家研究基金(RS-2021-NR060090);韩国国家研究基金(RS-2025-25442300)

Species heterogeneity for efficient electrocatalytic nitrate reduction to ammonia

Kefu Zhanga,1, Luxiao Zhanga,1, Jianyi Chua, Cenyu Meia, Siyuan Liua, Guilan Fana, Fenrong Liua, Youngkook Kwonb(), Fenghua Baia(), Wenhao Luoa()   

  1. a School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010020, Inner Mongolia, China
    b School of Energy and Chemical Engineering & Graduate School of Carbon Neutrality, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
  • Received:2025-10-29 Accepted:2025-12-29 Online:2026-06-18 Published:2026-05-18
  • Contact: *E-mail: ykwon@unist.ac.kr (Y. Kwon),
    f.h.bai@imu.edu.cn (F. Bai),
  • About author:

    1Contributed equally to this work.

  • Supported by:
    National Natural Science Foundation of China(22479082);National Natural Science Foundation of China(22562020);funding of Inner Mongolia University(10000-23112101/081);funding of Inner Mongolia Youth Science and Technology Talents(NJYT24019);funding of Local Science and Technology Development Guided by Central Government(2024ZY0116);Guangdong Province Key Field R&D Project(2023B0202010027);National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT(RS-2021-NR060090);National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT(RS-2025-25442300)

摘要:

电催化硝酸盐还原反应(NO3RR)是一种在环境条件下实现氨合成与废水净化的可持续途径. 该反应涉及复杂的多步质子耦合电子转移过程, 受限于缓慢的反应动力学以及与析氢反应之间的竞争, 因此, 开发兼具高活性与高稳定性的电催化剂, 是当前面临的核心挑战. 铁基催化剂因储量丰富且具备良好的本征催化活性而备受关注. 近期研究表明, 构建具有不同类型活性位点(如单原子与纳米团簇)的异质结构催化剂, 可通过位点间的协同效应实现该系列反应的高效串联. 然而, 如何精准控制负载型金属物种活性位点的异质性, 提高活性位点利用率并实现反应的高效偶联, 仍是该领域亟待突破的挑战.

本文展示了一种通过可控原位分解策略制备的碳负载的异质铁物种催化剂(Fe1+n/C), 该催化剂由孤立分散的铁单原子(Fe1)和超小尺寸铁纳米团簇(Fen)共同锚定在多孔碳载体上. 通过精准控制十二羰基三铁前驱体的热分解过程(热分解温度和升温速率), 实现异质铁物种, 即Fe1与Fen, 在三维多孔碳载体上的共同锚定. 通过 X射线衍射、球差校正高角环形暗场扫描透射电子显微镜、X射线光电子能谱等先进表征技术证实Fe1+n/C催化剂中异质Fe1与Fen活性位点的成功构筑. 为评估其在NO3RR中的性能, 在H型电解池中采用中性电解质开展系统的电化学测试. 性能对比结果表明, 与单一组分的Fe1/C和Fen/C催化剂相比, 这种异质结构催化剂在硝酸盐还原合成氨反应中表现出更加优异的催化性能, 在−0.80 V(相对于可逆氢电极)电位下实现了高达7889 μg mgcat−1 h−1的氨产率, 法拉第效率达到92.2%. 此外, Fe1+n/C催化剂在长达24 h的恒电位连续测试中表现出出色的稳定性, 电流密度与法拉第效率均未出现显著衰减. 结合原位红外光谱和密度泛函理论计算表明, Fe1位点促进硝酸盐吸附与脱氧过程, 而邻近的Fen位点则加速反应中间产物的后续氢化步骤. Fe1和Fen活性物种的协同耦合实现了高效的电子转移和逐步脱氧-氢化过程. 异质铁物种之间的协同串联促进了反应的高效耦合, 是提升整体催化性能的关键.

综上, 本工作不仅首次揭示了Fe物种活性位点的异质性对电催化NO3RR多步反应高效偶联的协同优势和重要性, 对推动绿色氨合成技术以及其它的发展具有重要意义; 并为设计多物种活性位点以促进串联电催化反应提供了一种普适性策略, 为设计用于电催化硝酸盐还原及其它能源转化与环境修复反应的高效异质结构催化剂提供了重要启示.

关键词: 电催化剂, 硝酸盐还原反应, 异质性, 铁, 单原子

Abstract:

Fe-based electrocatalysts are promising candidates for the electrochemical nitrate reduction reaction (NO3RR) owing to their earth abundance and favorable catalytic activity. However, controlling the intrinsic heterogeneity of supported metal species remains challenging, often limiting active-site utilization and high mass-specific activity. Here we demonstrate a heterostructured Fe1+n/C catalyst composed of atomically dispersed Fe single atoms (Fe1) and ultrasmall Fe nanoclusters (Fen) anchored on amorphous carbon via a controlled in-situ decomposition strategy. The synergistic coupling of Fe1 and Fen sites enables efficient electron transfer and stepwise deoxygenation-hydrogenation, delivering a high NH3 yield of 7889 μg mgcat−1 h−1 and a Faradaic efficiency of 92.2% at -0.80 V vs. RHE, outperforming single-species counterparts (Fe1/C and Fen/C). Density functional theory calculations reveal that Fe1 sites facilitate nitrate adsorption and deoxygenation, whereas Fen clusters promote hydrogenation of intermediates. This work uncovers the mechanistic origin of the synergistic effect in Fe-based heterogeneous catalysts and provides a general strategy for designing multi-species active sites to accelerate tandem electrocatalytic reactions.

Key words: Electrocatalysts, Nitrate reduction reaction, Heterogeneity, Fe species, Single-atom