Interface engineering to construct heterostructured SnS2/Sb2S3 on rGO through a targeted-complexation deposition strategy for high-performance lithium-ion capacitors

Abstract

Accurate synthesis of electrode materials with homogeneous heterostructure is an important approach to eliminate the energy storage dynamics discrepancy between the anode and cathode of lithium-ion capacitors (LICs). However, the complex synergistic effects between two electrodes is yet to materialize due to the lack of effective approach. Herein, a targeted-complexation deposition strategy is proposed to prepare uniform SnS2/Sb2S3 heterostructure attached to reduced graphene oxide (rGO) (SnS2/Sb2S3@rGO) with the aid of L-cysteine. The strong complexation between L-cysteine and metal ions effectively suppresses the hydrolysis reaction of Sb3+ ion and guides the uniform deposition of SnS2/Sb2S3 heterostructures on rGO. Due to the charge redistribution and mutual-support effect, the lithium storage properties of SnS2/Sb2S3@rGO can be integrated and greatly enhanced. Furthermore, a three-dimensional conductive network consisting of polyaniline and rGO heterostructure is synthesized by a self-assembly strategy, which is able to deliver a superior capacity of 178.6 mA h g−1 as well as outstanding rate property as a cathode. The LICs assembled with heterogeneous cathode and anode materials demonstrates an exceptional energy density (reaching 298 W h kg−1), impressive power density (58.5 kW kg−1) and remarkable capacity maintenance (78 %) even over 6000 cycles, providing a valuable guide for producing the high-performance LICs.