High-efficiency electrodeposition of polyindole nanocomposite using MoS2 nanosheets as electrolytes and their capacitive performance

Polyindole (PIn) has attracted extensive interest as promising energy storage materials owing to fairly good thermal stability, high redox activity and stability, however, it is challenging to prepare high-quality PIn in neutral solvents by electrochemical method. Herein, a simple route, based on MoS₂ nanosheets as electrolytes, has been developed for the electrochemical preparation of PIn/MoS₂ nanocomposite in acetonitrile solution. Due to the coordination interaction between indole and MoS₂, the onset oxidation potential of indole in this medium was reduced to 0.5 V from 0.75 V determined in acetonitrile/LiClO₄. The morphologies and structures of as-obtained PIn/MoS₂ nanocomposite were characterized using SEM, TEM, XRD, Raman and XPS. The results of thermal analysis indicated that the PIn/MoS₂ nanocomposite had an improved thermal stability relative to PIn and MoS₂ nanosheets. Moreover, the specific capacitance of PIn/MoS₂ nanocomposite was 8.3 times higher than that of PIn prepared acetonitrile/LiClO₄. To the best of our knowledge, this is the first report on the high-efficiency electrodeposition of PIn/MoS₂ nanocomposite in MoS₂-based acetonitrile solution, which will be a promising candidate as a high efficient electrode material in the application of supercapacitors.