Electrocatalysis for Continuous Multi-Step Reactions in Quasi-Solid-State Electrolytes Towards High-Energy and Long-Life Aluminum–Sulfur Batteries

Aluminum–sulfur (Al−S) batteries of ultrahigh energy-to-price ratios are a promising energy storage technology, while they suffer from a large voltage gap and short lifespan. Herein, we propose an electrocatalyst-boosting quasi-solid-state Al−S battery, which involves a sulfur-anchored cobalt/nitrogen co-doped graphene (S@CoNG) positive electrode and an ionic-liquid-impregnated metal–organic framework (IL@MOF) electrolyte. The Co−N₄ sites in CoNG continuously catalyze the breaking of Al−Cl and S−S bonds and accelerate the sulfur conversion, endowing the Al−S battery with a shortened voltage gap of 0.43 V and a high discharge voltage plateau of 0.9 V. In the quasi-solid-state IL@MOF electrolytes, the shuttle effect of polysulfides has been inhibited, which stabilizes the reversible sulfur reaction, enabling the Al−S battery to deliver 820 mAh g⁻¹ specific capacity and 78 % capacity retention after 300 cycles. This finding offers novel insights to design Al−S batteries for stable energy storage.