Cellulose-based hydrogels in flexible supercapacitors: A sustainable approach for energy storage solutions
Nurulhuda Azmi, Wan Azlina Wan Ab Karim Ghani, Shafreeza Sobri, Nur Izzah Nabilah Haris, Noor Ain Kamsani, Azil Bahari Alias
Abstract
The increasing global demand for sustainable and high-performance energy storage solutions has driven significant advancements in supercapacitor technology. This review explores the recent developments and breakthroughs in cellulose-based hydrogel electrolytes for flexible supercapacitors, focusing on their ability to enhance energy storage efficiency while promoting environmental sustainability. Innovations such as hybrid hydrogels combining cellulose with conductive materials , and the development of anti-freezing hydrogels for low-temperature operation have significantly improved the performance of these materials. Furthermore, enhancements in mechanical flexibility and strength , particularly through bacterial cellulose (BC) and cellulose nanocrystals (CNC), have expanded their application in wearable devices. The creation of self-healing hydrogels and tunable porosity for better ion transport further advances the durability and efficiency of these materials. Each type contributes specific properties that improve the mechanical flexibility, ionic conductivity , and overall electrochemical performance of supercapacitors. By integrating cellulose-based hydrogel electrolytes, flexible supercapacitors offer promising solutions for next-generation energy storage, aligning with the global shift toward renewable energy technologies.