Ultra-porous Co foam supported FeCoP electrode for high efficiency hydrogen evolution reaction

Development an alternative approach to efficiently and economically produce hydrogen from water to replace non-renewable fossil fuels is one of the great challenges in the energy field. In this paper, a Co foam (CF) with 90% porosity and pore size of a few tens of micrometers was prepared, on which FeCoP nanoflowers were in-situ formed. Such a combination was used as a new electrocatalyst/self-supporting electrode for high efficiency hydrogen evolution reaction. Thanks to the larger surface area (and thus many more active sites), and quicker mass transfer through the porous structure, the CF supported FeCoP electrode exhibited much better hydrogen evolution reaction (HER) performance than the commercial Ni foam supported counterpart prepared under identical conditions. In the case of the former, only -44 mV overpotential was required to achieve a geometric current density of -10 mA cm^-2, and the electrode showed a high stability at a current density < -500 mA cm^-2. The electrode developed in this work could be potentially used as a novel electrode for future large-scale production of hydrogen. In addition, the novel strategy reported here could be similarly used to develop many other types of self-supporting electrodes with further improved HER performance.