Exploring the underlying kinetics of electrodeposited PANI-CNT composite using distribution of relaxation times

Author(s)

Stott, Ash ^[1] ; Neto, Decio B. de Freitas ^[2] ; Rosolen, Jose M. ^[2] ; Sporea, Radu A. ^[1] ; Silva, S. Ravi P. ^[1]

Affiliation

^[1] Adv Technol Inst, Guildford GU2 7XH, Surrey - England

^[2] 1 Univ Sao Paulo, Fac Filosofia Cien Cias & Letras Ribeirao Preto, Dept Quim, Ave Bandeirantes 3900, BR-14040901 Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: Electrochimica Acta; v. 401, JAN 1 2022.
• Web of Science Citations: 0

Abstract

The Distribution of Relaxation Times (DRT) was successfully demonstrated in the analysis of the impedance spectra of a parametric series of composite polyaniline (PANI) coated carbon nanotubes (CNT) electrodes. DRT was then applied to the measured spectra and polarization processes were separated based on their typical time constants. The main processes were identified, and their contribution quanti-fied by analysing a set of electrodes with PANI deposited under various conditions, forming a parametric set. For the first time we have shown that DRT can be used to identify individual internal processes of complex composite electrodes without a priori knowledge of the system. This method offers a model-free approach for the study of EIS spectra and the characterization of resistive-capacitive systems. This was demonstrated by the optimisation of our PANI coated CNT electrodes which have exhibited a PANI specific capacitance of 772 F g - 1 and rate capability of 76% from 1 to 100 mV s - 1 . (c) 2021 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 17/50380-5 - Non woven carbon nanotube composite fiber electrodes for electrochemical energy conversion/storage devices
• Grantee: Jose Mauricio Rosolen
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/04759-2 - Free-binder electrodes for storage/conversion energy
• Grantee: Jose Mauricio Rosolen
• Support Opportunities: Regular Research Grants