Generating highly active Ni11(HPO3)8(OH)6/Mn3O4 catalyst for electrocatalytic hydrogen evolution reaction by electrochemical activation

The design of electrocatalysts with cost-efficient, highly-efficient and stable for hydrogen evolution reaction (HER) is significant to alleviate energy crisis in the future. Herein, we prepared the Ni-11(HPO3)(8)(OH)(3)/Mn3O4 (named as NiPi/Mn3O4) composite with crystalline/amorphous interface by electrochemical activation based on Ni3P/MnOOH precursor. The precursor was synthesized by two-step method that firstly electrodeposited on nickel foam and then used anodic oxidation under the applied voltage. The XPS analysis manifested that NiPi/Mn3O4 had a strong interface coupling between Ni-11(HPO3)(8)(OH)(3) and Mn3O4 contributed to fast kinetics of hydrogen evolution reaction. The morphology of the nanowires and nanoparticles were provided lager contact area between catalyst and electrolyte. Meanwhile, the obvious interface between crystalline and amorphous also resulted in NiPi/Mn3O4 heterostructureted material with faster electron transport and superior stability. Owing to these characteristics, the NiPi/Mn3O4 displays amazing HER activity with low overpotential of 84 mV at 100 mA cm(-2) and a long-term stability of over 100 h at 200 mA cm(-2) in 1.0 M NaOH solution. The surprising activity of NiPi/Mn3O4 is better than that of most reported catalysts, similar to the state-of-the-art Pt/C. (C) 2019 Elsevier Inc. All rights reserved.