Two-dimensional ultrathin networked CoP derived from Co(OH)2 as efficient electrocatalyst for hydrogen evolution

The application of hydrogen is one of the promising ways to alleviate the global energy pollution. However, the electrocatalytic hydrogen evolution is currently limited by the low hydrogen evolution reaction (HER) kinetics based on noble metals. Thus, it is in urgent need to develop non-noble metal based electrocatalysts with an enhanced catalytic efficiency and environment-friendly properties. In the present study, two-dimensional ultrathin CoP networked materials are successfully synthesized by a low-temperature phosphorylation method with ultrathin mesh cobalt hydroxide precursor. Electrochemical test demonstrates that CoP electrocatalyst (CoPOH120) needs only a small overpotential (12 mV) to achieve a current density as high as 10 mA cm(-2), which surpasses most of hydrogen evolution catalysts working in alkaline environment. Most significantly, the overpotential of CoPOH120 electrode only drops to 38 mV after 1000 cycles of cyclic voltammetry (CV), exhibiting marvelous cyclic stability. Our ultrathin two-dimensional networked CoP materials promise the applications for various electrochemical energy conversion and storage fields.

Automated summary

The application of hydrogen is a promising way to alleviate global energy pollution. However, the current electrocatalytic hydrogen evolution using noble metals is limited by low kinetics. Therefore, it is urgent to develop non-noble metal electrocatalysts with enhanced efficiency and environmental friendliness. In this study, two-dimensional ultrathin CoP networked materials were successfully synthesized and showed high current density and cyclic stability, suggesting their potential applications in various electrochemical energy conversion and storage fields.