A Thai team uses Azolla biomass as a common precursor for porous activated-carbon cathodes and hydrochar anodes in a sodium-ion capacitor, using 15 m NaClO4 water-in-salt electrolyte to extend the operating window to 2.3 V.
Key findings
- AZ_AC stored charge mainly by ion adsorption/desorption, while disordered AZ_HC with expanded spacing accommodated Na+. The 2.3 V cell reached 135 Wh/kg at 230 W/kg on active mass and retained 85.3% after 1,000 cycles.
Why this matters globally
Using fast-growing aquatic biomass for both carbon electrodes may valorize feedstock and reduce electrode-metal dependence. Aqueous electrolytes aid safety, while concentrated salts retain cost and environmental burdens.
Thai researcher contribution
Ubon Ratchathani University, Prince of Songkla University, and VISTEC combined biomass, carbon-material, and energy-storage expertise in a Thai-developed prototype.
Limitations to consider
Energy density excludes current collectors, separator, electrolyte, and packaging. One thousand cycles are limited; self-discharge, coulombic efficiency, temperature, abuse safety, batch variability, salt recovery, and LCA are not stated.