Black phosphorene modified polymer solid electrolyte membrane toward advanced all solid-state Li-S batteries

With high theoretical energy density and low cost, lithium‑sulfur batteries are viewed as next-generation energy storage technologies. But issues like the polysulfide shuttle effect and electrolyte safety concerns hinder their commercialization. Here, we present a novel cathode-supported black phosphorene modified composite polymer solid electrolyte membrane (CS-BP-CPSEM) made from polyethylene oxide-polyvinylidene fluoride polyblend and black phosphorene. Black phosphorene nanosheets, produced via electrochemically assisted liquid-phase exfoliation, are uniformly dispersed in the composite polymer matrix and directly multilayer tape-cast onto the cathode surface. This design improves interfacial contact and Li + transport. The optimized CS-BP-CPSEM with 0.3 wt% BP shows a 5.37 V electrochemical stability window and 1.3 × 10 −3  S cm −1 ionic conductivity at 60 °C. Polysulfide adsorption tests confirm black phosphorene's strong anchoring ability, effectively lessening the shuttle effect. Consequently, the assembled all solid-state lithium sulfur battery (ASSLSB) delivers a high discharge capacity of 1322 mAh g −1 and maintains 453 mAh g −1 after over 100 cycles at 0.05C. This work offers a promising interfacial engineering strategy using two-dimensional materials to boost high-energy-density and long-cycle-life solid-state Li-S battery development.