Redox Materials for Electrochemical Capacitors

• Published in: Denki kagaku oyobi kōgyō butsuri kagaku Vol. 92; no. 7; p. 074002
• Main Authors: CHIKU, Masanobu, ABDOLLAHIFAR, Mozaffar, BROUSSE, Thierry, CHEN, George Z., CROSNIER, Olivier, DUNN, Bruce, FIC, Krzysztof, HU, Chi-Chang, JEŻOWSKI, Paweł, MAĆKOWIAK, Adam, NAOI, Katsuhiko, OGIHARA, Nobuhiro, OKITA, Naohisa, OKUBO, Masashi, SUGIMOTO, Wataru, WU, Nae-Lih
• Format: Journal Article
• Language: English
• Published: Tokyo The Electrochemical Society of Japan 31-07-2024; Japan Science and Technology Agency
• Subjects: Capacitance; Capacitors; Chemical reactions; Electrochemical Capacitor; Electrochemistry; Manganese; Manganese oxides; Metal-organic frameworks; Nanomaterials; Nanotechnology; Nickel; Pseudo Capacitor; Redox Material; Redox reactions; Ruthenium; Ruthenium oxide; Transition metal oxides
• ISSN: 1344-3542; 2186-2451
• DOI: 10.5796/electrochemistry.24-70054

Electrochemical capacitors are known for their high power density and cyclability, and various redox reactions can be utilized to improve their energy density. A great variety of redox materials have been investigated recently for use in electrochemical capacitors, not only transition metal oxides, which have been studied for many years. In this review, we provide a comprehensive explanation of redox materials for electrochemical capacitors. Manganese oxides and ruthenium oxides, which are typical metal oxides exhibiting pseudocapacitance, are first discussed. Nickel oxides used in hybrid capacitors are also covered. Various 0D and 2D nanomaterials are highlighted. Pseudo-capacitance using nanosized complex materials and metal-organic frameworks is also presented. Furthermore, electrolyte systems that exhibit redox characteristics for electrochemical capacitors are also reviewed.