High-Entropy Local Microenvironment-Catalyzed Tandem Reaction Achieves Superfast Sodium Storage Anode.

Abstract

Sodium-ion batteries hold promising application potential in the field of low-speed electric vehicles. However, the sluggish kinetics and poor thermodynamic stability of conventional sodium-ion battery anode materials limit their applicability under fast-charging and long-cycle conditions. Herein, we propose a high-entropy multicomponent interface design paradigm to tailoring a unique (TiVCrNbTa)_0.2Se₂ (HE_0.2Se₂) anode. Leveraging the synergistic catalytic effect among high-entropy atoms to catalyze the tandem reaction and enable rapid phase transitions. Theoretical calculations reveal that local microenvironment of the high-entropy intrinsic structure reduces adsorption energy and diffusion barriers at metal-Se sites, enhances Na-ion mobility, and improves metal-Se bonding, thereby catalyzing tandem reaction and accelerating phase transition. Ex situ Raman spectroscopy, in situ XRD, and AC-TEM analyses further confirm the thermodynamic reversibility of the HE_0.2Se₂ electrode. At a high current density of 10 A g^-1, HE_0.2Se₂ delivers a specific capacity of 396.7 mAh g^-1 after 1000 cycles. And delivering specific capacities exceeding 310 and 200.8 mAh g^-1 at 50 A g^-1 and 100 A g^-1. Full-cell testing demonstrates excellent cycling stability, with the capacity remaining stable after 400 cycles. This study provides essential theoretical insights and an experimental foundation for designing ultrafast-charging anodes applicable to a variety of energy storage systems.