Exploring highly efficient and low-cost electrocatalysts is important for boosting the efficiency of water splitting to obtain clean and renewable energy. In this study, the NiFe layered double hydroxide nanosheets (NiFe-LDH NSs) have been developed on Ni nanowires (NWs) via the in situ assembly of oriented 2D nanosheets. Because of its unique composition and hierarchical NS@NW structure with the conductive Ni NW core as electron conduit, this material catalyst performs as a superior oxygen evolution reaction (OER) electrocatalyst, exhibiting a low onset overpotential of 230 mV in 1 M KOH. Remarkably, NiFe-LDH NSs can be readily converted to Fe-doped Ni2P nanosheets (Fe-Ni2P NSs) or Fe-doped NiSe2 nanosheets (Fe-NiSe2 NSs) upon phosphorization or selenization treatments, which are both excellent electrocatalysts toward hydrogen evolution reaction (HER) in alkaline solution. Consequently, two-electrode alkaline water electrolyzers have been constructed using NiFe-LDH NSs as anode and Fe-Ni2P NSs or Fe-NiSe2 NSs as cathode, which can afford a current density of 30 mA cm−2 at cell voltages of 1.69 V and 1.76 V, respectively, with excellent long-term durability.

Self-growing Ni-based hybrid nanosheet arrays on nanowires for overall water splitting

2019 Fall National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.