Proton Electroinsertion in Self-Assembled Materials for Neutralization Pseudocapacitors

Autor(es)

Facci, Tiago ^[1] ; Gomes, Wellington J. A. S. ^[1] ; Bravin, Bruno ^[1] ; Araujo, Diogenes M. ^[1] ; Huguenin, Fritz ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Quim, Fac Filosofia Ciencias & Letras Ribeirao Preto, BR-14040901 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Langmuir; v. 30, n. 1, p. 426-431, JAN 14 2014.
• Citações Web of Science: 10

Resumo

We propose novel pseudocapacitors that can store energy related to the partial entropy change associated with proton concentration variations following neutralization reactions. In this situation, it is possible to obtain electrochemical energy after the complete charge/discharge cycle conducted in electrolytic solutions with different proton concentrations. To this end, we prepared modified electrodes from phosphomolybdic acid (PMA), poly(3,4-ethylenedioxythiophene/poly(styrenesulfonate) (PEDOT-PSS), and polyallylamine (PAH) by the layer-by-layer (LbL) method and investigated their electrochemical behavior, aiming to use them in these neutralization pseudocapacitors. We analyzed the potentiodynamic profile of the current density at several scan rates, to evaluate the reversibility of the proton electroinsertion process, which is crucial to maximum energy storage efficiency. On the basis of the proposed reaction mechanism and by using frequency-domain measurements and models, we determined rate constants at different potentials. Our results demonstrated that the conducting polymer affects the self-assembled Medium matrixes, ensuring that energy storage is high (22.5 kJ mol(-1)). The process involved neutralization of a hydrochloric acid solution from pH = 1 to pH = 6, which corresponds to 40% of the neutralization enthalpy. (AU)

• Processo FAPESP: 12/21629-1 - Policianometalatos para baterias de mistura entrópica
• Beneficiário: Fritz Cavalcante Huguenin
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 11/21545-0 - Eletrocatalisadores para baterias de Li-ar
• Beneficiário: Fritz Cavalcante Huguenin
• Modalidade de apoio: Auxílio à Pesquisa - Regular