Electrostatic spun hierarchically porous carbon matrix with CoSe₂/Co heterostructure as bifunctional electrocatalysts for zinc-air batteries

N-doped carbon matrix with CoSe₂/Co heterostructures was fabricated via a four-step method by using electrostatic spinning technology for bifunctional electrocatalysts with affluent active sites, hierarchical porosity and outstanding electrocatalytic performance. The optimized CoSe₂/Co@NCNF-3 exhibited excellent bifunctional electrocatalytic performance with a Tafel slope of 76 mV/dec for ORR and a potential of 1.64 V vs. RHE at 10 mA/cm² for OER. Furthermore, it also showed superior long-term stability and anti-methanol ability compared to those of commercial Pt/C and IrO₂ catalysts. Application of CoSe₂/Co@NCNF-3 in zinc-air battery was assembled with distinguished long-term cycling stability and high maximum power density (79 mW/cm²). Density functional theory calculation demonstrated that CoSe₂/Co heterostructure boosted intermediate adsorption ability and also improved catalytic capacity for OER.