Ultrathick MoS<sub>2</sub> Films with Exceptionally High Volumetric Capacitance
Zheng Bo, Xiangnan Cheng, Huachao Yang, Xinzheng Guo, Jianhua Yan, Kefa Cen, Zhaojun Han, Liming Dai
Abstract
Abstract Manufacturing electrode films at an industrial‐level submillimeter thickness (≈100 µm) with superior volumetric performance is of practical significance for the commercialization of miniaturized supercapacitor systems. This work proposes a commercially scalable solvated‐ion‐intercalated hydrothermal strategy to demonstrate a record‐high volumetric capacitance (511.29 F cm −3 ) for supercapacitors based on an industrial‐level submillimeter MoS 2 film electrode (94.2 µm). The intercalated solvated Li + ions increase the amount of negative surface charge and reduce the formation energy of 1T MoS 2 , leading to a high metallic phase content of 82.7% with enhanced electrical conductivity. Together with the expanded interlayer distance (≈1.23 nm), this allows rapid electron transfer and ion transport in the excessively stacked ultrathick MoS 2 film to be simultaneously realized. Thus, the as‐fabricated MoS 2 ||graphene/carbon nanotube asymmetric supercapacitor presents both high energy and power densities, outperforms those of commercial devices, including supercapacitors with submillimeter‐thick electrodes and even micrometer‐thick electrodes.