2D metal phosphide loop-sheet heterostructures are controllably synthesized by edge-topological regulation, where Ni2P nanosheets are edge-confined by the N-doped carbon loop, containing ultrafine NiFeP nanocrystals (denoted as NiFeP@NC/Ni2P). This loop-sheet feature with lifted-edges prevents the stacking of nanosheets and induces accessible open channels for catalytic site exposure and gas bubble release. Importantly, these NiFeP@NC/Ni2P hybrids exhibit a remarkable oxygen evolution activity with an overpotential of 223 mV at 20 mA cm−2 and a Tafel slope of 46.1 mV dec−1, constituting the record-high performance among reported metal phosphide electrocatalysts. The NiFeP@NC/Ni2P hybrids are also employed as both anode and cathode to achieve an alkaline electrolyzer for overall water splitting, delivering a current density of 10 mA cm−2 with a voltage of 1.57 V, comparable to that of the commercial Pt/C||RuO2 couple (1.56 V). Moreover, a photovoltaic–electrolysis coupling system can as well be effectively established for robust overall water splitting. Evidently, this ingenious protocol would expand the toolbox for designing efficient 2D nanomaterials for practical applications.
All Science Journal Classification (ASJC) codes
- Materials Science(all)