Cost-Effective MIL-53(Cr) Metal–Organic Framework-Based Supercapacitors Encompassing Fast-Ion (Li⁺/H⁺/Na⁺) Conductors

A chromium-based low-cost metal–organic framework (MOF) cathode, MIL (Matériaux de l′Institut Lavoisier)-53(Cr), is coupled with a bioderived porous carbon (BPC) anode, produced from abundantly available agricultural waste betel nut shells in an asymmetric supercapacitor, for the first time. The impact of electrolyte on electrochemical behavior BPC//MIL-53(Cr) supercapacitor was assessed by constructing cells following electrolytes: proton-conducting camphorsulfonic acid (CSA), Li+-ion-conducting solutions LiClO4, Na+-ion-conducting sodium poly(4-styrene sulfonate) solution, and ionic liquid (IL:1-butyl-1-methyl-pyrrolidinium trifluoromethanesulfonate)-based solutions. aqueous H+-ion-based CSA shows superior conductivity (270 mS cm–1) enhanced transport number (0.96), carries larger currents, retains high even at subambient temperatures, clearly outperforming all other Li+/Na+/IL electrolytes. BPC/aqueous or LiClO4/MIL-53(Cr) supercapacitors show storage performances, H+ cell having specific capacitance 70 F g–1 energy power density maxima 9.7 Wh kg–1 0.25 kW enduring 104 cycles. detailed account dependence cation/anion- solvent-type charge provides basis adapting these design principles to developing high-performance MOF-based supercapacitors.