Sulfuric Acid‐Dissolved Cellulose‐Induced Toughened Polyvinyl Alcohol Hydrogel Electrolyte for Flexible Energy Storage
Polyvinyl alcohol (PVA)‐based hydrogel electrolytes are widely employed in flexible solid‐state supercapacitors owing to their biodegradability, nontoxicity, and low cost. However, the further application of pure PVA hydrogel is limited by its low mechanical properties, narrow electrochemical working window, and insu...