Rationally Modulating the Functions of Ni3Sn2-NiSnOx Nanocomposite Electrocatalysts towards Enhanced Hydrogen Evolution Reaction
Xiaomei Wang, Guifa Long, Bo Liu, Zelong Li, Wensheng Gao, Pengfei Zhang, Hong Zhang, Xia Zhou, Ruizhi Duan, Wei Hu, Can Li*
Angew. Chem.Int. Ed.
https://onlinelibrary.wiley.com/doi/epdf/10.1002/anie.202301562
Identifying electrocatalysts with functions of easy dissociation of water, rapid transformation of hydroxyl and facile hydrogen-hydrogen bond formation are indispensable while challenge for realizing efficient alkaline hydrogen evolution reaction (HER). Herein, we presented the design of Ni3Sn2-NiSnOx nanocomposites towards addressing this challenge. We showed that Ni3Sn2 possessed ideal hydrogen adsorption and low hydroxyl adsorption abilities and NiSnOx facilitated water dissociation and hydroxyl transfer process, respectively. Consequently, the fine-tuned interplay of the two functional parts realized the mutual coordination among the multiple functions and led to significantly boosted HER kinetics. Current densities of 10 and 1000 mA cm-2 were obtained at overpotentials of 14 and 165 mV on the optimized catalyst. This work highlights the significance of considering intrinsic interactions between active sites and all pertinent intermediates on obtaining promising electrocatalysts.
近日，我组在碱性析氢复合电催化剂理性设计方面取得新进展。工作聚焦活性功能组分和所涉及全部反应中间物种之间的内在关系，秉承兼顾催化剂氢吸附自由能、水吸附解离及氢氧物种脱附能力的原则，设计并构筑了Ni3Sn2-NiSnOx纳米复合电催化剂，用于高效催化碱性析氢（HER）反应。
碱性电解水制氢技术是实现可再生能源规模化制备“绿氢”的重要手段。发展廉价、高效、稳定的碱性电解水催化剂是该领域的核心之一。我组长期致力于电催化分解水及其水分解表面催化作用研究（Nat. Catal., 2018；ACS Catal., 2018；Nano Energy, 2018；Angew. Chem. Int. Ed., 2019；Small, 2022；Chem. Sci., 2022；J. Am. Chem. Soc., 2023），受到学术界广泛关注。此外，我组自主研发的新一代碱性电解水催化剂装配于千立方/小时电解水制氢装置，并应用于兰州新区千吨级太阳燃料工业化示范工程项目，受到工业界广泛关注。
本工作在深入理解和剖析碱性HER反应机理的基础上，聚焦于如何同时实现对水的吸附解离、氢的耦合脱附及氢氧物种的快速脱附等微观反应过程的理性调控这一关键问题，在镍基合金-氧化物复合催化剂体系的理性设计中引入了具有亲氧性低于Ni，且氢吸附能力也较弱的Sn元素，设计构筑了高效Ni3Sn2-NiSnOx纳米复合碱性析氢电催化剂体系。最优催化剂在电流密度为10, 500和1000 mA cm-2时，分别仅需过电位14, 111和165 mV。研究表明，Ni3Sn2具有适宜的氢吸附自由能及弱氢氧物种吸附能力，是一种理想的析氢活性组分；NiSnOx 组分则可有效加速水解离和 OHad 物种的转移传输过程。两个功能组分的微调相互作用可实现多个功能之间的相互协调，从而显著提升复合催化剂的碱性HER动力学，进而获得优异催化性能。该研究明确了聚焦催化剂活性功能组分和所涉及反应中间物种之间内在关系对于获得优异催化剂体系的重要性，可为今后电催化剂体系的理性设计工作提供借鉴。
相关研究成果以“Rationally Modulating the Functions of Ni3Sn2-NiSnOx Nanocomposite Electrocatalysts towards Enhanced Hydrogen Evolution Reaction”为题，于近日发表在《德国应用化学国际版》（Angewandte Chemie International Edition）上。该工作的第一作者为李灿院士指导的兰州大学萃英博士后王小梅。该工作得到国家自然科学基金、中国博士后面上项目的资助。（文/图 王小梅）
文章链接：https://onlinelibrary.wiley.com/doi/10.1002/anie.202301562
