Gravimetric and dynamic deconvolution of global EQCM response of carbon nanotube based electrodes by Ac-electrogravimetry

Freddy Escobar-Teran (1) , A. Arnau (2, 3) , J.V. Garcia (2, 3) , Y. Jiménez (2, 3) , Hubert Perrot (1) , Ozlem Sel (1)

1 LISE - Laboratoire Interfaces et Systèmes Electrochimiques
2 Polytechnic University
3 Advanced Wave Sensors S.L.

The capacitive charge storage of carbon nanotube (CNT) based electrodes was investigated by ac-electrogravimetry which couples fast quartz crystal microbalance (QCM) and electrochemical impedance spectroscopy (EIS). In contact with an aqueous NaCl electrolyte, evidence was found that there are two types of cations (Na + .H 2 O and H +) electroadsorbed with different kinetics for cathodic potentials and the Cl-ions for anodic potentials together with free water molecules. The reconstruction of the total mass response from independent ac-electrogravimetry measurements agrees perfectly well with the global EQCM response. Our findings reveal the unique sensitivity of the ac-electrogravimetry to provide a fair gravimetric and dynamic deconvolution of the global EQCM responses.

Mots clés: ac-electrogravimetry; EQCM; ion transfer dynamics; electroadsorption; Carbon nanotubes; supercapacitors

Domaines: Autre; Chimie

Freddy Escobar-Teran, A. Arnau, J.V. Garcia, Y. Jiménez, Hubert Perrot, et al.. Gravimetric and dynamic deconvolution of global EQCM response of carbon nanotube based electrodes by Ac-electrogravimetry. Electrochemistry Communications, 2016, 70, pp.73 - 77. ⟨10.1016/j.elecom.2016.07.005⟩. ⟨hal-01398611⟩