Properties of Electrode Materials and Electrolytes in Supercapacitor Technology

Abstract

This thorough review article offers a cutting-edge analysis of the essential characteristics and developments in electrode materials and electrolytes for supercapacitor technology. We start by going over the basics of supercapacitors and how important characterization methods like electrochemical impedance spectroscopy, galvanostatic charge-discharge, and cyclic voltammetry work. Specific capacitance, energy, and power densities, three essential characteristics that are crucial for assessing supercapacitor performance, are carefully covered in this work. We also analyze the many kinds of capacitors, including hybrid supercapacitors, electric double-layer capacitors, pseudocapacitors, and supercapacitors, and explain their working principles and material-specific characteristics. The study highlights the importance of metal oxides and hydroxides, carbon-based materials, conductive polymers, and novel and hybrid materials such as MXenes and metal-organic frameworks. The special qualities of each material class, such as large surface area, electrical conductivity, and particular redox properties, are highlighted in this section. These qualities are crucial for maximizing the performance of supercapacitors. The topic of electrode materials is discussed in detail, including their benefits and the difficulties and chances to improve energy storage, stability, and affordability. Parallel to this, the study thoroughly examines various electrolyte kinds, a sometimes overlooked yet essential part of supercapacitor technology. Discussed include ionic conductivity, operating voltage windows, safety profiles, and electrochemical stability of aqueous, organic, ionic liquid, gel, and solid-state electrolytes. This paper highlights the relationship between supercapacitor performance and electrolyte type, explaining how electrolyte selection affects total energy density, power density, and operational longevity. This review article covers supercapacitor technology in detail and with a wide scope and is an invaluable resource. It is a fundamental work for scholars and practitioners new to the area. It offers sophisticated insights that may encourage creativity and application-specific advancement in this quickly changing field. The study presents a comprehensive analysis of the present and future developments in supercapacitor materials and technology, establishing it as a vital resource in the continuous search for cutting-edge energy storage solutions.