Evaluation of the aniline chemical oxidation process using multiple simultaneous electrochemical responses

Author(s)

Cristovan, Fernando H. ^[1] ; Lemos, Sherlan G. ^[2] ; Santos, Janaina S. ^[1] ; Trivinho-Strixino, Francisco ^[1] ; Pereira, Ernesto C. ^[1] ; Mattoso, Luiz H. C. ^[3] ; Kulkarni, Rashmi ^[4] ; Manohar, Sanjeev K. ^[4]

Affiliation

^[1] Univ Fed Sao Carlos, Dept Quim, Lab Interdisciplinar Eletroquim & Ceram, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Fed Paraiba, Dept Quim, BR-58051970 Joao Pessoa, Paraiba - Brazil

^[3] Embrapa Instrumentacao Agropecuaria, Lab Nacl Nanotecnol Agronegocio, BR-13560970 Sao Carlos, SP - Brazil

^[4] Univ Massachusetts, Dept Chem Engn, Lowell, MA 01854 - USA

• Document type: Journal article
• Source: Electrochimica Acta; v. 55, n. 12, p. 3974-3978, APR 30 2010.
• Web of Science Citations: 4

Abstract

In this paper we show the simultaneous evaluation of the electrochemical impedance, the open circuit potential and the mass variation of the polyaniline deposited on a metal substrate during chemical oxidation of aniline. We detected that the final properties of the polymer could be practically defined after the inflection point of the potential profile. Considering a series connection of R and C. impedance Z was decomposed into the resistive and capacitive components. The resistivity and permittivity show a slight change after the inflection point in the potential profile. Impedance data and mass changes during synthesis also contributed to a better definition of the induction period. We described the system as whole, which relates to an electronic transport and to an electronic charge storage process. Although very simple, this model helps us to interpret and correlate different techniques to explain the results. In addition, we demonstrated that the in situ evaluation of the parameters described above offers new insights on the chemical synthesis mechanism of polyaniline. (C) 2010 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 05/00453-9 - Development of solid state sensors for determining inorganic contaminants in trace levels
• Grantee: Sherlan Guimarães Lemos
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 03/09933-8 - Center for Excellence in Electrochemically Synthesized Nanostructures
• Grantee: Ernesto Chaves Pereira de Souza
• Support Opportunities: PRONEX Research - Thematic Grants