Cheng Junfang, Nie Junyu, Li Xinyi, Huang Jiawei, Zhang Zuyu, Feng Ziye, Zhang Guozhu, Wu Rui, Shen Shuiyun, Wei Guanghua, Zhang Junliang
SJTU Paris Elite Institute of Technology, Shanghai Jiao Tong University, Shanghai 200240, China.
Shanghai Key Laboratory of Intelligent Sensing and Detection Technology, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 200237, China.
Langmuir. 2025 Mar 18;41(10):6872-6881. doi: 10.1021/acs.langmuir.4c05122. Epub 2025 Mar 4.
Developing highly efficient nonprecious metal catalysts for oxygen evolution reactions (OERs) is crucial for the development of water electrolysis; however, these catalysts face challenges such as high overpotential and insufficient durability at high current densities. In this study, we successfully prepared ordered needlelike structured Co-Fe hydroxide with F-ion immersion (Fe/Co(OH)F) on the surface of nickel foam and explored the synergistic strengthening effects of Mo cation doping and P anion doping. The ordered needlelike structure of Fe/Co(OH)F was destroyed during the phosphating calcination process, while Mo doping transformed it into a rough surface platelike structure. By combining Mo doping with phosphating treatment, the obtained Fe/F-MoCo-PO catalyst presented a crystalline-amorphous heterostructure and platelike morphology with enhanced OER performance. At a high current density of 200 mA cm, the Fe/F-MoCo-PO catalyst exhibited an overpotential of 300 mV without i-R compensation and maintained a potential decay rate of only 0.16 mV h after a 560 h durability test. Electrochemical testing combined with phase structure and composition analysis revealed that P doping induced the formation of an amorphous surface layer of hypophosphite Fe(PO), which was found to undergo anion exchange with *OH during electrochemical testing. This surface reconstruction thus formed a rich -OH catalytic layer on the surface of Fe/F-MoCo-PO, which then exhibited a remarkably lowered overpotential and boosted OER kinetics, surpassing most state-of-the-art OER electrocatalysts. This finding underscores the synergistic effect of Mo and P doping in forming a crystalline-amorphous heterostructure, which boosts alkaline OER performance, aiding in cost reduction and improvement of the hydrogen production efficiency through water electrolysis at high current densities.
开发用于析氧反应（OER）的高效非贵金属催化剂对于水电解的发展至关重要；然而，这些催化剂面临诸如高过电位和在高电流密度下耐久性不足等挑战。在本研究中，我们成功地在泡沫镍表面制备了具有F离子浸渍的有序针状结构的Co-Fe氢氧化物（Fe/Co(OH)F），并探索了Mo阳离子掺杂和P阴离子掺杂的协同强化效应。Fe/Co(OH)F的有序针状结构在磷化煅烧过程中被破坏，而Mo掺杂将其转变为粗糙的表面片状结构。通过将Mo掺杂与磷化处理相结合，所获得的Fe/F-MoCo-PO催化剂呈现出结晶-非晶异质结构和片状形态，其OER性能得到增强。在200 mA cm的高电流密度下，Fe/F-MoCo-PO催化剂在没有i-R补偿的情况下表现出300 mV的过电位，并且在经过560 h耐久性测试后仅保持0.16 mV h的电位衰减率。电化学测试结合相结构和成分分析表明，P掺杂诱导形成了次磷酸铁（Fe(PO)）的非晶表面层，发现在电化学测试期间该表面层与*OH发生阴离子交换。这种表面重构因此在Fe/F-MoCo-PO表面形成了富含-OH的催化层，然后该催化层表现出显著降低的过电位并促进了OER动力学，超过了大多数最先进的OER电催化剂。这一发现强调了Mo和P掺杂在形成结晶-非晶异质结构方面的协同效应，该效应提高了碱性OER性能，有助于降低成本并提高通过高电流密度下的水电解制氢效率。
