Electroactive 1T-MoS<sub>2</sub> Fluoroelastomer Ink for Intrinsically Stretchable Solid-State In-Plane Supercapacitors
Kaliannan Thiyagarajan, Woo‐Jin Song, Hyeji Park, Selvaraj Veerapandian, Sungmin Moon, Joosung Oh, Myung‐Jun Kwak, Gyeongbae Park, Minsik Kong, Monalisa Pal, Junghyeok Kwak, Anupam Giri, Ji‐Hyun Jang, Soojin Park, Unyong Jeong
Abstract
Full advantage of stretchable electronic devices can be taken when utilizing an intrinsically stretchable power source. High-performance stretchable supercapacitors with a simple structure and solid-state operation are good power sources for stretchable electronics. This study suggests a new type of intrinsically stretchable, printable, electroactive ink consisting of 1T-MoS2 and a fluoroelastomer (FE). The active material (1T-MoS2/FE) is made by fluorinating the metallic-phase MoS2 (1T-MoS2) nanosheets with the FE under high-power ultrasonication. The MoS2 in the 1T-MoS2/FE has unconventional crystal structures in which the stable cubic (1T) and distorted 2H structures were mixed. The printed line of the 1T-MoS2/FE on the porous stretchable Au collector electrodes is intrinsically stretchable at more than ε = 50% and has good specific capacitance (28 mF cm–2 at 0.2 mA cm–2) and energy density (3.15 mWh cm–3). The in-plane all-solid-state stretchable supercapacitor is stretchable at ε = 40% and retains its relative capacity (C/Co) by 80%. This printable device platform potentially opens up the in-plane fabrication of stretchable micro-supercapacitor devices for wearable electronic applications.