Scalable Solution Processing MoS2 Powders with Liquid Crystalline Graphene Oxide for Flexible Freestanding Films with High Areal Lithium Storage Capacity

ACS Appl Mater Interfaces. 2019 Dec 18;11(50):46746-46755. doi: 10.1021/acsami.9b15371. Epub 2019 Dec 3.

Abstract

Freestanding flexible electrodes with high areal mass loading are required for the development of flexible high-performance lithium-ion batteries (LIBs). Currently they face the challenge of low mass loading due to the limited concentrations attainable in processable dispersions. Here, we report a simple low-temperature hydrothermal route to fabricate flexible layered molybdenum disulfide (MoS2)/reduced graphene oxide (MSG) films offering high areal capacity and good lithium storage performance. This is achieved using a self-assembly process facilitated by the use of liquid crystalline graphene oxide (LCGO) and commercial MoS2 powders at a low temperature of 70 °C. The amphiphilic properties of ultralarge LCGO nanosheets facilitates the processability of large-size MoS2 powders, which is otherwise nondispersible in water. The resultant film with an areal mass of 8.2 mg cm-2 delivers a high areal capacity of 5.80 mAh cm-2 (706 mAh g-1) at 0.1 A g-1. This simple method can be adapted to similar nondispersible commercial battery materials for films fabrication or production of more complicated constructs via advanced fabrication technologies.

Keywords: MoS2 powders; flexible electrodes; high mass loading; liquid crystalline graphene oxide; lithium-ion batteries.