High-Entropy Transition Metal Phosphorus Trichalcogenides for Rapid Sodium Ion Diffusion.

High-entropy strategies have been regarded as a powerful means to confer desirable and enhanced functionalities in energy storage fields. The improved properties are invariably ascribed to entropy stabilization or synergistic cocktail effect. Therefore, the manifested properties in such disordered multicomponent materials are usually unpredictable. Elucidating the precise correlations between atomic structures and properties remains a challenge in high-entropy materials (HEMs). Herein, we combine atomic-resolution scanning transmission electron microscopy annular dark field (STEM-ADF) imaging and four dimensions (4D)-STEM to directly visualize atomic-scale structural and electric information in high-entropy FeMnNiVZnPS 3 . We found aperiodic stacking in FeMnNiVZnPS 3 accompanied by high-density strain soliton boundaries (SSBs). Theoretical calculation suggests that the formation of such structures is attributed to the imbalanced stress of distinct metal-sulfur bonds in multi-element systems. Interestingly, the electric field concentrates along the two sides of interface regions and gradually diminishes towards the two-dimensional plane to generate unique electric field gradient, strongly promoting the ion diffusion rate. Accordingly, high-entropy FeMnNiVZnPS 3 demonstrates superior ion-diffusion coefficients of 10 -9.7 -10 -8.3 cm 2 s -1 and high-rate performance (311.5 mAh g -1 at 30 A g -1 ). This work provides an alternative way for the atomic-scale understanding and design of sophisticated HEMs, paving the way for property engineering in complex multi-component materials. This article is protected by copyright. All rights reserved.