Efficient and stable Ni-Co-Fe-P nanosheet arrays on Ni foam for alkaline and neutral hydrogen evolution

摘要

The development of highly efficient and superior durability electrocatalysts is vital to expedite hydrogen evolution reaction (HER). Herein, a mixed amorphous and nano-crystalline Ni-Co-Fe-P alloy on Ni foam after 75 s dealloying in 3 M HCl (Ni-Co-Fe-P/NF-3-75) is synthesized by the preparation strategy of two-step method consisting of electroless deposition and dealloying process. Ni-Co-Fe-P/NF-3-75 shows an excellent HER performance and high durability in both alkaline and neutral conditions by optimizing the composition of the catalysts, acid concentration, and the time of dealloying. Benefitting from the high conductivity of Ni foam carrier, coordination between polymetallic phases, and the large exposure of defects, the as-prepared Ni-Co-Fe-P/NF-3-75 requires only a low overpotential of 56 mV and 104 mV to reach the current density of 10 mA cm(-2) in 1.0 M KOH and 1.0 M phosphate buffer (PBS), respectively. Remarkably, the Ni-Co-Fe-P/NF-3-75 electrode exhibits superior cycling stability and long-term robust durability without obvious overpotential decline. The successful preparation of the Ni-Co-Fe-P/NF-3-75 catalyst indicates that this method provides an efficient way to synthesize polymetallic phosphides for hydrogen evolution reaction. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.