2D MoS<sub>2</sub> Nanosheet‐Based Polyimide Nanocomposite with High Energy Density for High Temperature Capacitor Applications
Jiayuan Li, Jinxi Zhang, Shuangzhe Zhang, Kailiang Ren
Abstract
Abstract With the development of electrical vehicles and power electronics, the demand for high‐temperature energy storage capacitors with high energy density has grown rapidly. In this investigation, 2D MoS 2 nanosheets are coated with a thin layer of poly(methyl methacrylate) and then mixed with polyimide (PI) solution to fabricate nanocomposites. The dielectric constant of MoS 2 ‐g‐PMMA/PI (MPP‐3%) reaches 4.2, which is 20% higher than that of a pristine PI film. The energy density of the MPP‐3% nanocomposite reaches 8.6 J cm −3 , which is 40% higher than the highest energy density of a pristine PI film. In addition, the electric breakdown field of the MPP‐3% composite is 50% higher than that of the MoS 2 /PI nanocomposite without a surface coating. Furthermore, it is found that the highest energy density of MoS 2 ‐g‐PMMA/PI reaches 3.92 J cm −3 , which is 47.9% higher than that of the PI film at 150 °C. The charge–discharge efficiency of the nanocomposite film reaches 61.7% at 150 °C. This result is much higher than the previously reported research results for high‐temperature capacitor applications. The MoS 2 ‐g‐PMMA/PI‐based nanocomposite shows great promise for use in high‐temperature capacitor applications.