Trace Tungsten and Iron Doped Nickel Hydroxide Nanosheets for Efficient Oxygen Evolution Reaction
FexNi1-x(O)OH has been proved to be a efficient, earth-abundant and nonprecious catalysts for oxygen evolution reaction (OER). However, the weak binding of oxygenated intermediates and few active sites exposure on NiFe hydroxide badly limit its catalytic activity. Based on the fact that W6+ ions possess higher vacancy and similar ionic radius compared with Fe2+, Fe3+, Ni2+ ions, which can modulate (NiO6) crystal structure and enhance block electrons interaction, we try to introduce trace amount of W6+ into FexNi1-x(O)OH. To our surprise, the target product Fe0.03W0.03-Ni LDHB exhibits the lowest overpotential of 205(±3) mV at 10 mA cm−2, Tafel slope of 60 mV dec−1, as well as no obvious decrease electrocatalytic activity after more than 50-hours operation or 3000 times cyclic voltammetry. X-ray diffraction, Raman, UV-vis spectrum, X-ray photoelectron spectroscopy and electro-chemical studies reveal a synergistic interplay between tungsten, iron and nickel in producing a favorable local coordination environment and electronic structure that enhance the OER performance.