Liang Jiabang, Liu Yu, Wang Zegao, Jia Yifan, Ding Zhao, Gao Liangjuan
College of Materials Science and Engineering, Sichuan University, Chengdu, 610065, China.
College of Materials Science and Engineering, National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing, 400044, China.
Discov Nano. 2025 Jul 15;20(1):112. doi: 10.1186/s11671-025-04283-x.
The urgent need for bi-functional high-performance non-noble metal-based catalysts for water splitting requires the integration of both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) together, which not only increases the energy efficiency but also reduces fabrication cost. However, most non-noble metal-based catalysts for OER are not stable under alkaline conditions, while HER shows poor kinetic performance under alkaline conditions, which prevents the water splitting from scale-up applications. Therefore, in this paper, non-noble metal-based catalyst of NiS@MoO@CoO@AMO/NF was prepared by a two-step hydrothermal method followed by a galvanic replacement reaction with morphological characterization, demonstrating that the synthesized material has a core-shell structure. The electrochemical properties of NiS@MoO@CoO@AMO/NF were tested and analyzed, which confirmed its efficient electrocatalytic activity. The catalyst exhibited excellent OER in 1 M KOH solution, and a low overpotential of 248 mV was achieved at a current density of 10 mA cm. In addition, the catalyst maintained competitively low overpotentials even at high current densities, 281 mV and 303 mV at 50 mA cm and 100 mA cm, respectively. Remarkably, only an overpotential of 185 mV was required to reach the current density of 10 mA cm for HER. The excellent OER and HER performances could be attributed to the synergistic effects among AMO, CoO and MoO. In addition, NiS@MoO@CoO@AMO/NF required only 1.414 V at 10 mA cm to complete the overall water splitting and exhibited excellent competitiveness also at high current densities (1.769 V and 1.975 V at 50 mA cm and 100 mA cm, respectively). The morphology of NiS@MoO@CoO@AMO remained stable after long time i-t tests, which proved its long-term operational stability. The Faraday efficiencies of the OER and HER could reach 75.92% and 97.51%, respectively, which showed excellent electrocatalytic performance. Therefore, the synthesis of high-performance bifunctional catalysts based on a two-step hydrothermal reaction followed by a galvanic replacement reaction proposed in this study provides a new strategy for the simple and efficient synthesis of non-noble metal-based catalysts for high-performance overall water splitting.
迫切需要用于水分解的双功能高性能非贵金属基催化剂，这要求将析氧反应（OER）和析氢反应（HER）整合在一起，这不仅能提高能源效率，还能降低制造成本。然而，大多数用于OER的非贵金属基催化剂在碱性条件下不稳定，而HER在碱性条件下的动力学性能较差，这阻碍了水分解的规模化应用。因此，本文通过两步水热法，随后进行电置换反应，制备了具有形貌表征的NiS@MoO@CoO@AMO/NF非贵金属基催化剂，证明合成材料具有核壳结构。对NiS@MoO@CoO@AMO/NF的电化学性能进行了测试和分析，证实了其高效的电催化活性。该催化剂在1 M KOH溶液中表现出优异的OER性能，在电流密度为10 mA cm时实现了248 mV的低过电位。此外，即使在高电流密度下，该催化剂也能保持较低的过电位，在50 mA cm和100 mA cm时分别为281 mV和303 mV。值得注意的是，HER达到10 mA cm的电流密度仅需185 mV的过电位。优异的OER和HER性能可归因于AMO、CoO和MoO之间的协同效应。此外，NiS@MoO@CoO@AMO/NF在10 mA cm时仅需1.414 V即可完成全水分解，在高电流密度下（50 mA cm和100 mA cm时分别为1.769 V和1.975 V）也表现出优异的竞争力。经过长时间的i-t测试，NiS@MoO@CoO@AMO的形貌保持稳定，证明了其长期运行稳定性。OER和HER的法拉第效率分别可达75.92%和97.51%，显示出优异的电催化性能。因此，本研究提出的基于两步水热反应随后进行电置换反应合成高性能双功能催化剂，为简单高效合成用于高性能全水分解的非贵金属基催化剂提供了一种新策略。
