Melanin as additive in hydrogel electrolytes for application in supercapacitors

• Grant number: 23/14464-0
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: May 01, 2024
• End date: April 30, 2025
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Carlos Frederico de Oliveira Graeff
• Grantee: João Victor Morais Lima
• Supervisor: Hadis Zarrin
• Host Institution: Faculdade de Ciências (FC). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil
• Institution abroad: Toronto Metropolitan University (TMU), Canada
• Associated to the scholarship: 21/03379-7 - Application of New Materials as Electrodes in Flexible Supercapacitors, BP.DR

Abstract

Flexible supercapacitors (FSCs) are one of the most promising electrochemical energy storage devices due to their high-power density, high temperature range and long cycle life. The fabrication of FSCs demands the use of electrolytes with high ionic conductivity, flexible and with low interfacial resistance between the electrode and the electrolyte. The most common types of electrolytes used for this application are gels electrolytes. However, this type of electrolyte still has some challenges, such as its low ion conductivity. Thus, the synthesis of new high-performance electrolytes has been a focus among researchers. The use of redox-active materials as an additive has been a promising strategy to obtain electrolytes with high ionic conductivity and high-performance devices. Melanin is a material that has been highly explored in pseudocapacitive energy storage systems due to the various redox forms of its structure, metal chelating property and high ionic conductivity. In this context, this project proposes, for the first time, the study of water-soluble melanins as an additive in hydrogels for application as electrolyte in FSCs. The hydrogels used will be based on carboxymethylcellulose/citric acid or based on polyvinyl alcohol. Thus, the influence of the physical, chemical, electrochemical, and rheological characteristics of the hydrogels on the characteristics of the FSCs will be evaluated in terms of specific capacitance, energy and power density, and life cycle.