Sci. China Mater. - Atomically-Dispersed Platinum Supported onto Nanoneedle-Shaped Protonated Polyaniline for Efficient Hydrogen Production in Acidic Water Electrolysis

Zhenzhong Wu, Jing Bai, Feili Lai, Hui Zheng, Yizhe Zhang, Nan Zhang, Chuanxi Wang, Zhenyu Wang, Longsheng Zhang*, Tianxi Liu*

Science China Materials 2023, DOI: 10.1007/s40843-022-2414-2

Developing high-performance single-atom platinum (Pt) catalysts for acidic hydrogen evolution reaction (HER) is of significance. However, their HER kinetics are limited due to the low concentration of hydrogen ions (H⁺) near the Pt sites in acidic electrolytes, where hydronium ions are undesirably formed with H⁺ surrounded by water molecules. Here, we seek to improve the HER kinetics by anchoring single-atom Pt catalyst on nanoneedle-shaped protonated polyaniline supports, which can not only capture H⁺ from the hydronium ions but also facilitate the electroreduction of H⁺ by promoting the electron accumulation. As a result, the turnover frequency of single-atom Pt supported on the nanoneedle-shaped protonated polyaniline is appreciably enhanced, compared with that of the single-atom Pt supported on the flat-shaped protonated polyaniline. By combining the X-ray photoelectron spectroscopy, finite-element simulation and electrochemical studies, we find that the enhanced HER activity of single-atom Pt on nanoneedle-shaped protonated polyaniline support may arise from a hydrogen spillover pathway induced by the increased local concentration of H⁺ near the Pt sites.

Link: https://doi.org/10.1007/s40843-022-2414-2