کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5150534 1498237 2017 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Impedance spectroscopy studies of proton conductivity in imidazolium malonate
موضوعات مرتبط
مهندسی و علوم پایه شیمی الکتروشیمی
پیش نمایش صفحه اول مقاله
Impedance spectroscopy studies of proton conductivity in imidazolium malonate
چکیده انگلیسی
Imidazolium malonate ɱstands out from other proton conducting compounds of nitrogen containing heterocyclic bases with dicarboxylic acids due to a presence of both ordered and disordered imidazolium in the crystal lattice. Our impedance spectroscopy studies of electric conductivity revealed that in the range 273 K ≤ T ≤ 318 K the dc conductivity is characterized by an activation energy of Ea1 = 0.50 eV and the activation energy decreases to Ea2 = 0.17 eV at temperatures 318 K ≤ T ≤ 358 K. Single crystal X-ray diffraction studies showed that imidazolium malonate has the same triclinic structure with P-1 space group and rather high thermal displacements factors at 280 K as well as at 340 K. The results suggest that the low-temperature activation energy can be ascribed to phonon assisted 180° flipping of ordered imidazolium cations, observed earlier in NMR experiments. The 'fast-like diffusion' of protons in the high temperature range we consider to be due to the presence of disordered imidazolium cations enhanced by high thermal displacements.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Solid State Ionics - Volume 306, August 2017, Pages 25-30
نویسندگان
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