Recent Advances in Transition Metal Chalcogenides for Flexible Supercapacitors

Abstract

Layered transition metal chalcogenides have always been an area of ample interest in the field of electronics for their fascinating photo responsiveness and well-documented physical, chemical, and thermal properties. While their tunable thickness-dependent bandgap forms the core of its wide employment in solar cells, sulfides and selenides of various metals have shown brilliant electrochemical functionality as electrode materials in supercapacitors, the main reason being their high responsiveness to redox reactions and their ability to form two-dimensional sheet-like nanostructures capable of intercalating electrolyte ions. There is ample scope for study regarding the energy storage potential of chalcogenides, which has already been treated promisingly and needs further fine-tuning of parameters. Supercapacitors have been termed as “future” energy storage devices as they can store a high amount of energy in contrast to batteries and would be an indispensable necessity for miniaturized, portable, lightweight consumer devices in the coming days. The novelty here arises in incorporating structural flexibility with the high energy density of supercapacitors by using different flexible substrates for the growth of nanostructured electrodes with suitable materials. Different metal chalcogenides are emerging as possible candidates for flexible supercapacitors providing better capacitance and long-term stability. This chapter provides comprehensive insights into flexible supercapacitors fabricated out of chalcogenides, pivotal to the development of environment-friendly, user-friendly, emerging-energy storage devices. Here, we covered the role and importance of metal chalcogenides as electrode materials in supercapacitors, different synthesis procedures adapted so far for their fabrication, the characterization techniques employed to test their functionality, and finally, gave an account of the work that has been so far done in this field on flexible versus nonflexible substrates. In this regard, the chapter presents a significant insight to the readers interested in working in this latest and growing aspect and enlightening them on the same so that research on different flexible supercapacitors from chalcogenides finds inspiration to sustainable use in the recent future.