SiOC functionalization of MoS2 as a means to improve stability as sodium-ion battery anode

Abstract

The development of feasible, scalable, and environmentally-safe electrode materials that provide stable cycling performance are critical for success of beyond lithium rechargeable batteries and supercapacitors. With respect to the sodium-ion battery (SIB) anodes constituting of transition metal dichalcogenides such as molybdenum disulfide (MoS2), poor cycle stability and fast capacity degradation, due to low electronic conductivity and dissolution of chemical species in the electrolyte, hinders use of these promising layered materials as SIB anodes. Herein we report chemical functionalization in MoS2 nanosheets with polymer-derived silicon oxycarbide or SiOC with the aim to preserve MoS2 from dissolution in the SIB organic electrolyte, without compromising its role in sodiation and desodiation processes. Our results suggest that a MoS2–SiOC composite electrode is effective in bringing improved cycle stability to sodium-ion cycling over neat MoS2 even after 100 cycles.