Advanced Two-Dimensional Layered Compound-Based Materials for High Performance Lithium/Sodium-Ion Capacitors

Abstract

Lithium/sodium-ion capacitors (LICs/SICs), based on the combination of Faradaic characteristics and capacitance behavior of a hybrid electrochemical storage mechanism, are expected to realize better power density and cycle life than lithium/sodiumion batteries and higher energy density than supercapacitors. However, the serious mismatch of electrochemical reaction kinetics of the battery-type anode controlled by sluggish solid-state diffusion and the capacitor-type cathode depending on rapid surface ion adsorption restricts their electrochemical performance. Pseudocapacitance, as a bridge between traditional doublelayer capacitors and typical rocking chair batteries, can bridge the gap between power and energy density. Up to now, two-dimensional layered materials with controllable nanosheet structure, large interlayer distance, and expectable tunable intercalation have shown considerable pseudocapacitive behaviors. In this paper, the recent progress in the research of advanced two-dimensional layered compound-based anode materials for LICs/SICs with controllable tuning of pseudocapacitive responses realized by effective strategies for material design is reviewed. This paper also discusses the challenges and possible developing trends for the future development of twodimensional high pseudocapacitance anode materials in building high energy and power density LICs/SICs.