Reverse Modulation of Carbon-Interface Electron Density via s-d Block High-Entropy-Alloys Boosts Li-S Batteries

Carbon materials, renowned for their exceptional intrinsic properties, play a pivotal role in the domain of lithium-sulfur batteries, especially for encasing delicate metal-based catalysts. However, this encasement hinders the precise control of catalytic capacity because carbon's inherent σ-bonding complicates direct changes to the material's surface atomic and electronic structure. Herein, a universal fresh perspective is reported that remotely and precisely reverse manipulation the surface electronic structure of carbon host by driving electron pumping, accumulation, Li ion diffusion and facilitate covalent interactions with polysulfides using s-d block high-entropy-alloys (CoNiCuMnMg@C). Theoretical calculation optimization results confirm that polysulfides stabilize at the Carbon interface rather than directly at the alloy surface so as to avoid its being poisoned. Density functional theory (DFT) calculations and KPFM results shed light on that coupling with high-entropy-alloys, especially with highly exotic Mg, reduces the work function and enhances the electron density signaling that an electron deviation from alloy to C (Hershfield charge of -0.34 e), which in turn enhances the electron-rich carbon's ability to strongly adsorb Li⁺. The CoNiCuMnMg@C catalyst boosts Li⁺ diffusion and accelerate the redox kinetics of polysulfides. The CoNiCuMnMg@C/S cathode exhibits excellent initial specific capacity and capacity retention. This novel strategy provides new horizons for high-effective catalyst design.