Designing High-Performance Symmetric Supercapacitors from Waste Jute and Bio-Electrolyte

The performance of porous carbon (PC)-based supercapacitor especially the energy density for the most part is dependent on its electrolytic system. Sodium sulfate (Na 2 SO 4 ) is the most studied neutral aqueous electrolyte system studied so far for the PC-based electric double-layer capacitors (EDLC). But the theoretical value for the working potential of Na 2 SO 4 is limited to only 1.23 V, and hence it limits the energy density of the storage system. Here, we are reporting the fabrication of a supercapacitor electrode derived from waste jute using the bio- electrolyte sodium acetate (SA) as an alternative to the Na 2 SO 4 electrolyte. Due to its unique physicochemical properties, the 0.5 M SA electrolyte could successively be able to expand (0.5 V) the working potential of the fabricated supercapacitor. Thus, the system achieved almost four times higher energy density when using SA electrolyte instead of Na 2 SO 4 . The SA electrolyte-based EDLC showed an outstanding specific capacitance of 213 Fg -1 at 1 Ag -1 current density were retaining 92% capacitance even after 10,000 cycles.