Cobalt oxide-porous carbon composite derived from CO2 for the enhanced performance of lithium-ion battery

•Co3O4/Carbon composite was synthesized via one thermal step at 1 atm.•CO2 was used as both carbon source and oxidizing agent simultaneously.•Co3O4 nanoparticles are evenly inserted in the porous carbon layer.•The composite stably retained 1179 mA h g−1 at 1 A g−1 over 300 cycles.