Developing a stable and high-performance W-CoMnP electrocatalyst by mitigating the Jahn-Teller effect through W doping strategy

Recently, a research team led by Professor Ge Lei from China University of Petroleum (Beijing) developed a simple template-free method to prepare cobalt-based and manganese-based precursors, and then doped W during the synthesis of transition bimetallic phosphides to obtain the W-doped bimetallic phosphides. The resulting catalyst exhibits excellent bifunctionality and can can be utilized as an electrode in anion exchange membrane (AEM) water electrolyzers. The research results have been published in the Chinese Journal of Catalysis.

W-CoMnP exhibits excellent oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) performance, with relatively low overpotentials of 225 mV at 50 mA cm^-2 (OER) and 95 mV at 10 mA cm^-2 (HER). In addition, when the catalyst was evaluated as a bifunctional electrode, its cell voltage was as low as 1.52 V and lasted for more than 24 hours. In order to realize its commercial application, W-CoMnP was assembled into an anion exchange membrane (AEM) water electrolysis device, which can achieve continuous and stable hydrogen production under room temperature conditions.

Both electrostatic field theory and DFT theoretical calculations show that the electron density generated by the MOF method is more concentrated, thereby adjusting the electronic structure of W-CoMnP and generating unsaturated Co atoms and Mn atoms, thereby creating oxygen atom capture sites for the adsorption of W-CoMnP. Through the exploration of the Jahn Teller effect mechanism, controlling the spin state (S) of the Mn³⁺ cation provides a basic strategy to alleviate the Jahn-Teller distortion and enhance the stability of Mn-based materials. For Mn³⁺, two spin configurations can be assumed in W-CoMnP, including a high spin state (t_2g³e_g¹, S=2) and a low spin state (t_2g⁴e_g⁰, S=1). W doping changes the electronic spin state of Mn to a low spin state, and the electrons of Mn3+ occupy all t_2g energy levels and carry spin decay electrons, resulting in the failure of the Jahn Teller effect of Mn3+ in CoMnP, thereby allowing the material to exert its performance.

The study used a tungsten doping strategy to stabilize manganese-based bimetallic phosphide (W-CoMnP), effectively inhibiting the Mn³⁺ disproportionation and Mn²⁺ dissolution caused by the Jahn-Teller effect, and significantly improving the electrocatalytic activity and stability. The material exhibited excellent HER (η₁₀ = 95 mV) and OER (η₅₀ = 225 mV) performance, and achieved efficient and stable hydrogen evolution at 1.52 V in the AEM water electrolyzer, demonstrating its broad prospects in practical applications.

The results were published in Chinese Journal of Catalysis (DOI: 10.1016/S1872-2067(25)64669-9)

About the journal

Chinese Journal of Catalysis is co-sponsored by Dalian Institute of Chemical Physics, Chinese Academy of Sciences and Chinese Chemical Society, and it is currently published by Elsevier group. This monthly journal publishes in English timely contributions of original and rigorously reviewed manuscripts covering all areas of catalysis. The journal publishes Reviews, Accounts, Communications, Articles, Highlights, Perspectives, and Viewpoints of highly scientific values that help understanding and defining of new concepts in both fundamental issues and practical applications of catalysis. Chinese Journal of Catalysis ranks among the top six journals in Applied Chemistry with a current SCI impact factor of 17.7. The Editors-in-Chief are Profs. Can Li and Tao Zhang.

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