Progressively Exposing Active Facets of 2D Nanosheets toward Enhanced Pseudocapacitive Response and High-Rate Sodium Storage

Adv Mater. 2019 Apr;31(17):e1900526. doi: 10.1002/adma.201900526. Epub 2019 Mar 11.

Abstract

Sodium-ion batteries are gradually regarded as a prospective alternative to lithium-ion batteries due to the cost consideration. Here, three kinds of tin (IV) sulfide nanosheets are controllably designed with progressively exposed active facets, leading to beneficial influences on the Na+ storage kinetics, resulting in gradient improvements of pseudocapacitive response and rate performance. Interestingly, different forms of kinetics results are generated accompanying with the morphology and structure evolution of the three nanosheets. Finally, detailed density functional theory simulations are also applied to analyze the above experimental achievements, proving that different exposed facets of crystalline anodes possess dissimilar Na+ storage kinetics. The investigation experiences and conclusions shown in this work are meaningful to explore many other proper structure design routes toward the high-rate and stable metal-ions storage.

Keywords: 2D nanosheets; active facets; pseudocapacitance; sodium storage; tin (IV) sulfide.