• Fe/Ni-N-PCNSs exhibit exceptional performance as a dual host for sulfur and lithium, achieving a record low capacity decay of 0.00025% per cycle over 1000 cycles in Li-S batteries.
• The 2D porous structure and uniform Fe/Ni doping enable efficient polysulfide capture and fast redox kinetics, effectively suppressing the shuttle effect.
• Enhanced lithiophilicity of the material promotes uniform lithium nucleation, preventing dendrite growth and enabling stable cycling over 850 hours in lithium metal batteries.
• The template-free synthesis method offers a scalable and cost-effective approach for producing multifunctional carbon nanosheets for advanced energy storage.