Facile and green synthesis of 3D honeycomb-like N/S-codoped hierarchically porous carbon materials from bio-protic salt for flexible, temperature-resistant supercapacitors

•N/S-codoped hierarchically porous carbon materials are facilely and greenly prepared.•The combined method of double soft-template and solvent-free self-assembly is proposed.•3D honeycomb-like hierarchical pore structure is conducive to high-efficient energy storage.•The excellent temperature-resistance and flexibility exist.•High capacitance (302 F g−1) and 99% capacitance retention for 5000 cycles are shown.