A novel binder-free cathode catalyst Cu@NCNF/CP with three-dimensional self-supporting structure for Li-CO2 battery

•Cu@NCNF/CP as binder-free cathode catalyst with interconnection structure promotes electron transfer and Li ion migration.•Nitrogen doping process produces rich active sites, which promotes the uniform loading of Cu nanoparticles.•The self-supporting three-dimensional structure of Cu@NCNF/CP offers sufficient space for Li2CO3 to deposit.•Cu@NCNF/CP catalyst exhibits superior CO2RR and CO2ER activity for high-performance Li-CO2 batteries.