Blossoming of Multivalent Iron Phosphate Microplatelets Grown on Multiwall Carbon Nanotube Frameworks: Investigation of Supercapacitive Performance through Symmetric and Asymmetric Configurations

The present study explores the impact of non-toxic andhigher oxidationstate iron phosphate-blossomed microplatelets [Fe-7(PO4)(6)] anchored on multiwall carbon nanotubes (MWCNTs)toward supercapacitor applications, which is not only the first reportfor the synthesis of Fe-7(PO4)(6) bychemical bath deposition but also for the design of symmetric andasymmetric supercapacitive devices. Dip and dry coatedMWCNTs on the copper have been employed as the substrate to fabricatethe Cu/MWCNTs/Fe-7(PO4)(6) electrode.Interestingly, the designed Cu/MWCNTs/Fe-7(PO4)(6) electrode exhibited superior capacitance (727 F/g)compared to bare MWCNTs (49.8 F/g) and Fe-7(PO4)(6) (147.8 F/g) at 100 mV/s scan rate. The standalone electrodehas been well optimized through diverse characterizations followedby the fabrication of a symmetric device in an aqueous KOH electrolyte yielding 227 F/g specific capacitance, whereas an asymmetric solid-statedevice assembled using Cu/MWCNTs/Fe-7(PO4)(6) and SS/MWCNT electrodes with a conducting KOH electrolyteembedded in a non-conducting PVA polymer matrix yielding 163 F/g.Complete studies of symmetric and asymmetric devices have been incorporatedherein.

Automated summary

This study investigates the use of non-toxic and higher oxidation state iron phosphate-blossomed microplatelets [Fe-7(PO4)(6)] anchored on multiwall carbon nanotubes (MWCNTs) for supercapacitor applications. The study successfully synthesizes Fe-7(PO4)(6) using chemical bath deposition and designs symmetric and asymmetric supercapacitive devices. The Cu/MWCNTs/Fe-7(PO4)(6) electrode exhibited superior capacitance compared to bare MWCNTs and Fe-7(PO4)(6) at a scan rate of 100 mV/s.