A divided potential driving self-discharge process for single-walled carbon nanotube based supercapacitors

Abstract

Understanding the self-discharge (SDC) mechanism is crucial for obtaining supercapacitors with tunable energy retention. Supercapacitors built with free standing single-walled carbon nanotube (SWNT) macro-films and 1M TEABF₄/PC electrolyte exhibit a unique divided potential driving SDC discharge process as demonstrated by the perfect fitting results of the SDC curves under different charge current densities and at different SDC temperatures. The divided potential driving SDC process could be attributed to the existence of various functional groups attached to the SWNT surface from the purification process, through intervening and creating relatively weak bonds between the electrolytic ions and the SWNT electrode surface.