Phosphorylated Co(OH)2@NiFe-LDH core–shell heterostructure for highly efficient alkaline water splitting

Abstract

The development of transition metal bifunctional electrocatalysts with high activity, stability and cost-effectiveness is necessary for the overall water decomposition. In this work, a phosphorylated core–shell heterostructure bifunctional catalytic material with a nickel foam carrier, a Co(OH)2 nanowire array core and an ultrathin NiFe layered double hydroxide (NiFe-LDH) shell is synthesized. The solid contact between the NiFe-LDH shell and the highly conductive Co(OH)2 core brings about excellent electrical connectivity and an integrated hierarchical nanostructure that greatly improves the active specific surface area. Meanwhile, the phosphorylated hierarchical core–shell nanostructure enables the presence of a large amount of amorphous material at the edges, which leads to excellent activity and stability for oxygen evolution reactions (OER) and hydrogen evolution reactions (HER).