Integrating trifunctional Co@NC-CNTs@NiFe-LDH electrocatalysts with arrays of porous triangle carbon plates for high-power-density rechargeable Zn-air batteries and self-powered water splitting

A structural engineering strategy is proposed to fabricate trifunctional electrocatalysts supported by carbon cloth, composed of NiFe-LDH nanosheets aligned on Co-embedded N-doped carbon triangle plates with interwoven carbon nanotubes (Co@NC-CNTs@NiFe-LDH), which is employed as a freestanding electrode for both flexible Zn-air batteries and self-powered water splitting. This unique 3D hierarchical structure and the strong interfacial coupling between the NiFe-LDH and Co@NC-CNTs facilitate the transport of oxygen species as well as electrons and achieve synergy between the integrated nano-scaled structures with different functional components. As expected, a large peak power density of 194 mW cm−2 and outstanding durability for 760 h are obtained in the as-assembled rechargeable Zn-air battery. The resultant water splitting device acquires a cell voltage of 1.66 V at 10 mA cm−2 and the as-assembled Zn-air battery has been successfully employed in a self-power water splitting system, demonstrating a great potential prospect for practical renewable energy applications.