TY - JOUR
T1 - Study of Proton Transport in Diethylmethylammonium Poly[4-styrenesulfonyl(trifluoromethylsulfonyl)imide]-Based Composite Membranes with Triflic Acid and Diethylmethylamine-Rich Compositions
AU - Shah, Azhar Hussain
AU - Rana, Usman Ali
AU - Zhu, Haijin
AU - Li, Jiaye
AU - Vijayaraghavan, R.
AU - Macfarlane, Douglas R.
AU - Forsyth, Maria
AU - Siddiqi, Humaira M.
N1 - Publisher Copyright:
© 2021 American Chemical Society.
PY - 2021/10/7
Y1 - 2021/10/7
N2 - The study highlights the effect of acid- and base-rich conditions on the proton dynamics of diethylmethylammonium poly[4-styrenesulfonyl(trifluoromethylsulfonyl)imide, [DEMA][PSTFSI], a polymerized protic ionic liquid designed as a polymer electrolyte for nonhumidified polymer electrolyte membrane fuel cells. Different proportions of triflic acid (HTf) and diethylmethylamine (DEMA) were added to the pristine polymer. The thermal analysis of the mixtures revealed that the addition of the base increases the glassy/amorphous nature of the polymer; however, HTf plasticizes the polymer and lowers the Tg value, so that it falls outside of the differential scanning calorimetry-studied temperature range. 50 mol % doping of the HTf contents increases the conductivity upto 0.952 mS cm-1, and 50 mol % DEMA mixture has a conductivity of 0.169 mS cm-1 at 100 °C. Vogel-Tamman-Fulcher fitting of the ionic conductivities of the doped systems suggested that the ionic conductivities are completely decoupled from segmental motion of the polymer. A combination of Fourier transform infrared and static NMR studies demonstrated that HTf-added polymer composites show conduction via Grotthuss and vehicular mechanisms, while DEMA-added polymer composites show predominantly a Grotthuss mechanism by developing the aggregates of proton and added base.
AB - The study highlights the effect of acid- and base-rich conditions on the proton dynamics of diethylmethylammonium poly[4-styrenesulfonyl(trifluoromethylsulfonyl)imide, [DEMA][PSTFSI], a polymerized protic ionic liquid designed as a polymer electrolyte for nonhumidified polymer electrolyte membrane fuel cells. Different proportions of triflic acid (HTf) and diethylmethylamine (DEMA) were added to the pristine polymer. The thermal analysis of the mixtures revealed that the addition of the base increases the glassy/amorphous nature of the polymer; however, HTf plasticizes the polymer and lowers the Tg value, so that it falls outside of the differential scanning calorimetry-studied temperature range. 50 mol % doping of the HTf contents increases the conductivity upto 0.952 mS cm-1, and 50 mol % DEMA mixture has a conductivity of 0.169 mS cm-1 at 100 °C. Vogel-Tamman-Fulcher fitting of the ionic conductivities of the doped systems suggested that the ionic conductivities are completely decoupled from segmental motion of the polymer. A combination of Fourier transform infrared and static NMR studies demonstrated that HTf-added polymer composites show conduction via Grotthuss and vehicular mechanisms, while DEMA-added polymer composites show predominantly a Grotthuss mechanism by developing the aggregates of proton and added base.
UR - http://www.scopus.com/inward/record.url?scp=85117118660&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcb.1c04399
DO - 10.1021/acs.jpcb.1c04399
M3 - 文章
C2 - 34570507
AN - SCOPUS:85117118660
SN - 1520-6106
VL - 125
SP - 11005
EP - 11016
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 39
ER -