Insights into the intrinsic capacity of interlayer-expanded MoS2 as a Li-ion intercalation host

Abstract

Hierarchical MoS₂ hollow nanospheres with expanded interlayer spacing are synthesized and used as intercalation hosts to clarify the role of interlayer engineering in enhancing the Li-ion storage capacity. The interlayer-expanded MoS₂ possesses a high capacity of 220 mA h g⁻¹ at 1C rate, nearly 32% higher than the theoretical capacity of pristine MoS₂ (167 mA h g⁻¹). Electrochemical characterization clarifies unambiguously that this increased capacity mainly originates from the increased Li-ion intercalation amount due to the enlarged interlayer spacing. The related mechanism is illustrated by density functional theory calculations and the universality is inspected on micro-sized MoS₂. This study gives a clear insight into the intrinsic capacity of interlayer-expanded MoS₂ as a Li-ion intercalation host, which can facilitate the further development of high performance MoS₂-based electrodes.