Trimetallic Metal-Organic Framework Derived Carbon-Based Nanoflower Electrocatalysts for Efficient Overall Water Splitting

Searching desirable cost-effective electrocatalysts for overall water splitting is of great importance for the hydrogen production industry. Here a facile synthesis of trimetallic carbon nanoflower electrocatalysts is reported which are derived from Co2+/Fe2+/Ni2+ ratio adjustable metal-organic frameworks (MOFs). The unique nanosheet-assembled multiscale nanoflower morphology can enlarge the catalyst/electrolyte contact area, and the synergistic electronic effects between trimetallic components endow the trimetallic carbon nanoflower electrocatalysts with more oxygen vacancies and a higher degree of graphitization of carbon, thus showing excellent activity. The optimized Co0.2Fe0.8Ni-OCNF reaches a current density of 10 mA cm(-2) at low overpotential of 291 mV with a very small Tafel slope of 36.1 mV dec(-1) and 1.65 V@10 mA cm(-2) for a two-electrode water electrolysis in an alkaline solution, outperforming the commercial IrO2 electrocatalysts. The results may pave the way to the development of more efficient multicomponent nanosheet-assembled multiscale nanomaterials for various catalytic applications.