Variable and intelligent catalyst design based on local chemical environments in sulfur redox reactions

Abstract

The conventional constant catalyst design approach demonstrates limited adaptability to external conditions, impairing the catalytic performance in practical lithium-sulfur (Li-S) batteries. Here, we propose a variable and intelligent catalyst design strategy based on catalysts’ local chemical environments (LCEs). The competing adsorption between polysulfides and solvents within LCEs governs the interfacial reactions, regulated by the interaction between extrinsic electrolyte effects and intrinsic catalyst structures. Using nickel sulfides as a model system, interpretable machine-learning methods provide intelligent insights into structural tuning. Reversed catalytic efficiency is observed in LCEs of diluted and concentrated polysulfides, and variable catalyst modification guidance is presented for accelerating electron and ion transfer rates, respectively. Li-S batteries based on a Ni₃S₂ catalyst manifest exceptional performance in a lean electrolyte, achieving an energy density of 433 Wh kg⁻¹ in pouch cells. This investigation provides a thorough design protocol for catalysts and promotes practical applications of Li-S batteries through catalytic conversion.