Growing Intact Membrane by Tuning Carbon Down to Ultrasmall 0.37 nm Microporous Structure for Confining Dissolution of Polysulfides Toward High‐Performance Sodium–Sulfur Batteries

Room temperature sodium–sulfur (Na–S) batteries are severely hampered by dissolution of polysulfides into electrolytes. Herein, a facile approach is used to tune biomass-derived carbon down an ultrasmall 0.37 nm microporous structure for the first time as cathode in batteries. This produced intact uniform Na2S membrane greatly confine while realizing direct solid phase conversion complete reduction sulfur Na2S, which delivers loading 1 mg cm−2 (50 wt.%), excellent rate capacity (933 mAh g−1 @ 0.1 A and 410 2 g−1), long cycle performance (0.036% per decay at after 1500 cycles), high energy density 373 Wh kg−1 (0.1 g−1) based on whole electrode weight (active + carbon), ranking best among all reported plain cathode-based room terms life capacity. It proposed that pores (0.37 nm) can be squeezed out grow surface covering outlet depressing effect life. work provides green chemistry recycle wastes sustainable energies sheds light design unique pore effectively block high-performance