Hollow cobalt phosphate microspheres for sustainable electrochemical ammonia production through rechargeable Zn–N2 batteries

Hollow cobalt phosphate microspheres derived from cobalt phosphonates exhibit remarkable bifunctional NRR–OER electrocatalytic activity, and can serve as an efficient cathode catalyst of rechargeable Zn–N₂ batteries for electrochemical N₂-to-NH₃.