Electrochemical energy storage in organic supercapacitor via a non-electrochemical proton charge assembly

Abstract

Contrary to the conventional beliefs, we show how a ligand functionality that do not exhibit any redox activity, elevate the charge storage capability of the electric double layer via a proton charge assembly. The non-redox active carboxy ligand compared to the unsubstituted ligand demonstrated nearly 4 times elevated charge storage, impressive capacitive retention even at 900C rate and ~2 times lowered leakage currents with an enhancement in energy density up to ~70% via a non-electrochemical route of proton charge assembly. Generalizability of these findings are presented with various non redox active functionalities that can undergo proton charge assembly in the ligand. This demonstration of non-redox active functionalities enriching the super capacitive charge storage via proton charge assembly contributes to the rationale design of ligands for energy storage applications.