3.2 Pasantías y ponencias

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https://hdl.handle.net/20.500.12390/361

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Examinando 3.2 Pasantías y ponencias por Autor "rp00536"
  • Publicación
    Carboxymethyl kappa/iota-hybrid carrageenan doped with NH4I as a template for solid bio-electrolytes development
    (Elsevier B.V., 2019)
    Torres, FG
    ;
    Arroyo, J
    ;
    Alvarez, R
    ;
    Rodriguez, S
    ;
    Troncoso, O
    ;
    Lopez, D
    In this study, we analyzed the contribution of NH4I and glycerol on the ionic conductivity of carboxymethyl κ/ι-hybrid carrageenan-based solid bio-electrolytes. Electrochemical impedance spectroscopy was used to assess the electrochemical properties of the developed biopolymeric films and their interfaces over a wide range of frequencies (1& Hz–7& MHz). X-ray diffractograms demonstrated the increment of the amorphous fraction in the material as the NH4I content increases, suggesting an enhancement of ion transport processes and the successful incorporation of the salt into the host matrix. The shift of the OH peaks in the FTIR spectra confirmed the interaction between carboxymethyl carrageenan, NH4I, and glycerol. EIS results were represented in the complex plane and were fitted to an Rs(R1Q1) equivalent circuit. The ionic conductivity for carboxymethyl carrageenan doped with xNH4I (x = 15& wt%, 25& wt%, 35& wt%) and glycerol (15& wt%, 25& wt%) increased at higher salt and plasticizer content. This behavior was explained in terms of salt association/dissociation processes. The maximum ionic conductivity found in this study was 3.9& ×& 10−3& S/cm at room temperature. This result suggests that modified carrageenan-based materials can be suitable for the development of solid bio-electrolytes for electrochemical and energy storage applications. © 2018 Elsevier B.V.
  • Publicación
    Carboxymethyl κ/ι-hybrid carrageenan doped with NH4I as a template for solid bio-electrolytes development
    (Elsevier Ltd, 2019)
    Torres F.G.
    ;
    Arroyo J.
    ;
    Alvarez R.
    ;
    Rodriguez S.
    ;
    Troncoso O.
    ;
    López D.
    In this study, we analyzed the contribution of NH4I and glycerol on the ionic conductivity of carboxymethyl κ/ι-hybrid carrageenan-based solid bio-electrolytes. Electrochemical impedance spectroscopy was used to assess the electrochemical properties of the developed biopolymeric films and their interfaces over a wide range of frequencies (1& Hz–7& MHz). X-ray diffractograms demonstrated the increment of the amorphous fraction in the material as the NH4I content increases, suggesting an enhancement of ion transport processes and the successful incorporation of the salt into the host matrix.
  • Publicación
    Molecular dynamics of carboxymethyl kappa/iota-hybrid carrageenan films doped with NH4I
    (Taylor & Francis, 2019)
    Torres, FG
    ;
    Arroyo, J
    ;
    Alvarez, R
    ;
    Rodriguez, S
    ;
    Troncoso, O
    ;
    Lopez, D
    The effect of carboxymethylation and NH4I incorporation on the molecular dynamics of carrageenan films was studied. Broadband Dielectric Spectroscopy (BDS) assessed the presence of α and β relaxation processes. The effect of NH4I content was analyzed using the Havriliak-Negami model and parameterizing the temperature dependence of the relaxation times according to the Vogel-Fulcher-Tammann-Hesse (VFTH) equation. The glass transition temperature was found to decrease with the increase of NH4I content. These results suggest that carboxymethylation and the salt doping treatment increase the molecular mobility of NH4+ ions, making the films suitable for the development of solid electrolytes for energy storage applications. © 2018, © 2018 Taylor & Francis Group, LLC.