Energy storage has become increasingly important as a study area in recent decades. A growing number of academics are focusing their attention on developing and researching innovative materials for use in energy storage systems to promote sustainable development goals. This is due to the finite supply of traditional energy sources, such as oil, coal, and natural gas, and escalating regional tensions. Because of these issues, sustainable renewable energy sources have been touted as an alternative to nonrenewable fuels. Deployment of renewable energy sources requires efficient and reliable energy storage devices due to their intermittent nature. High-performance electrochemical energy storage technologies with high power and energy densities are heralded to be the next-generation storage devices. Transition metal chalcogenides (TMCs) have sparked interest among electrode materials because of their intriguing electrochemical properties. Researchers have revealed a variety of modifications to improve their electrochemical performance in energy storage. However, a stronger link between the type of change and the resulting electrochemical performance is still desired. This review examines the synthesis of chalcogenides for electrochemical energy storage devices, their limitations, and the importance of the modification method, followed by a detailed discussion of several modification procedures and how they have helped to improve their electrochemical performance. We also discussed chalcogenides and their composites in batteries and supercapacitors applications. Furthermore, this review discusses the subject’s current challenges as well as potential future opportunities.

Supercapacitors may be able to store more energy while maintaining fast charging times; however, they need low-cost and sophisticated electrode materials. Developing innovative and effective carbon-based electrode materials from naturally occurring chemical components is thus critical for supercapacitor development. In this context, biopolymer-derived porous carbon electrode materials for energy storage applications have gained considerable momentum due to their wide accessibility, high porosity, cost-effectiveness, low weight, biodegradability, and environmental friendliness. Moreover, the carbon structures derived from biopolymeric materials possess unique compositional, morphological, and electrochemical properties. This review aims to emphasize (i) the comprehensive concepts of biopolymers and supercapacitors to approach smart carbon-based materials for supercapacitors, (ii) synthesis strategies for biopolymer derived nanostructured carbons, (iii) recent advancements in biopolymer derived nanostructured carbons for supercapacitors, and (iv) challenges and future prospects from the viewpoint of green chemistry-based energy storage. This study is likely to be useful to the scientific community interested in the design of low-cost, efficient, and green electrode materials for supercapacitors as well as various types of electrocatalysis for energy production.

The development of low-cost, high-efficiency electrode materials for supercapacitors is motivated by the growing need for green and affordable clean energy (SDG goal 7). Developing new energy conversion and storage technologies, such as supercapacitors, batteries, and fuel cells, is a viable option for meeting energy demands while addressing environmental concerns. Recent advances in carbonaceous materials derived from biowaste for supercapacitor applications have piqued the interest of academics and industry alike. Because of their large surface area and porous structure, activated carbon-based electrode materials can be used in various applications, including supercapacitors, fuel cells, and batteries. Carbonaceous materials such as carbon nanotubes, graphene, and activated carbon, exhibit EDLC-like behavior mainly due to ion adsorption at the electrode interface. In recent years, several potential strategies for the synthesis and structural architecture of biowaste-derived porous carbons have been tested with varying degrees of success. Thus, it is critical to evaluate the prospects for biowaste-derived porous carbon materials used as supercapacitor electrodes. In this review, we highlight how different biowaste-derived porous carbon affects the surface properties of carbon nanostructures and how this affects their electrochemical performance. Additionally, the extent to which various biowastes have been utilized as porous carbon for supercapacitor electrodes is addressed. The different synthesis techniques, such as hydrothermal carbonization, physical activation, chemical activation, and microwave-assisted activation, are briefly described in this review. Finally, we highlight fabrication techniques as well as electrochemical performance measurements such as CV, GCD, EIS, energy density, and power density.

Climate change, primarily caused by the burning of conventional fossil fuels for energy generation has been one of the major challenges confronted by our current generation. To deal with this canker, research has been focused on the development of cost-effective, reliable, efficient, and eco-friendly energy generation and storage systems to match the increasing energy demand. Flexibility, high performance, and mechanical robustness are among the major requirements for portable, smart, and wearable electronic devices. 2D thin-film materials have proven to possess these properties, most importantly, the number of electrons confined in these 2D planes accounts for the inherent unmatched electronic performance. This chapter presents the most recent thin film deposition techniques used in the synthesis of 2D nanomaterials for energy conversion/storage applications. Materials, synthesis methods, and characterization techniques for thin-film 2D nanomaterials have all been thoroughly discussed. In particular, the utilization of these nanomaterials in various energy generation and storage applications has been highlighted in this chapter.

Supercapacitors (SCs), typically referred to as ultracapacitors or electrochemical capacitors, have demonstrated potential as the most promising candidate for energy storage devices to meet the demands for mankind's sustainable progress owing to their improved properties such as superior long cycle stability, power density, and low-cost processing. In recent years, conducting polymers (CPs) have been researched for supercapacitor applications as they combine the interesting properties of conventional polymers and the unique electronic properties of metals or semiconductors. This chapter seeks to introduce several conducting polymers such as polythiophene (PTh), polypyrrole (PPy), and polyaniline (PANI) as well as their applications in the area of supercapacitors. The various structural properties (from bulk to nanostructure) of conducting polymers and their performance as electrode components for supercapacitors have been discussed. Besides, composite-conducting polymers that contain different nanomaterials, such as graphene, carbon nanotubes, paramagnetic metal ions, and other carbon-based materials from both natural and synthetic polymers and their applications for supercapacitors are discussed.