N-Coordinated Iridium–Molybdenum Dual-Atom Catalysts Enabling Efficient Bifunctional Hydrogen Electrocatalysis
Jingbo Shi, Li Ren, Jianting Zhang, Yi Wang, Weilong Ma, Zongye Yue, Cheng‐Hao Jin, Yijiang Liu, Lirong Zheng, Jinbo Bai, Xiaolin Li, Kunyue Leng, Yunteng Qu
Abstract
Achieving effective hydrogen evolution/oxidation reaction (HER/HOR) across a wide pH span is of critical importance in unlocking the full potential of hydrogen energy but remains intrinsically challenging. Here, we engineer the N-coordinated Ir–Mo dual atoms on a carbon matrix by ultrafast high-temperature sintering, creating an efficient bifunctional electrocatalyst for both HER and HOR in both acidic and alkaline electrolytes. The optimized catalyst, Ir–Mo DAC/NC, demonstrates exceptional performance, with a significantly reduced HER overpotential of 11.3 mV at 10 mA/cm 2 and a HOR exchange current ( i 0,m ) of 3972 mA/mg Ir in acidic conditions, surpassing the performance of Pt/C and Ir/C catalysts. In alkaline conditions, Ir–Mo DAC/NC also outperforms Pt/C, as evidenced by its low HER overpotential of 23 mV at 10 mA/cm 2 and a high i 0,m of 1308 mA/mg Ir . Furthermore, our catalyst exhibits remarkable stability in both acidic and alkaline environments. DFT calculations results reveal that the superior electrochemical performance of Ir–Mo DAC/NC arises from the electronic synergy between Ir and Mo pairs, which regulates the interaction between the intermediates and active sites. These findings present a promising strategy for the development of dual-atom catalysts (DACs), with potential applications in the polymer fuel cells and water electrolyzers.