کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1298880 1498394 2007 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Low temperature synthesis of nanocrystalline proton conducting BaZr0.8Y0.2O3 − δ by sol–gel method
موضوعات مرتبط
مهندسی و علوم پایه شیمی الکتروشیمی
پیش نمایش صفحه اول مقاله
Low temperature synthesis of nanocrystalline proton conducting BaZr0.8Y0.2O3 − δ by sol–gel method
چکیده انگلیسی

Nanoceramic powders of proton conducting BaZr0.8Y0.2O3 − δ (BZY20) have been prepared at low crystallization temperature (below 130 °C) by sol–gel synthesis using all-alkoxide route. Due to a very low crystallization temperature, hydroxyl defects in the lattice crystal are incorporated in-situ during the synthesis process as confirmed by the gradual decrease in the lattice constant from 4.227 to 4.200 Ǻ on annealing from X-ray diffraction (XRD) analysis, OH vibrations observed in the diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis, and weight loss and heat exchange reaction observed by TG/DTA analysis. The results of XRD have revealed well-crystallized BZY20 peaks of this advanced ceramic material even at low processing temperature. Analysis of FT–Raman spectrum taken at room temperature for the nanocrystalline BZY20 samples prepared at 130 °C using sol–gel processing has revealed an ideal Pm3m cubic crystal symmetry. However, a very slight distortion due to the difference in the B-site sublattice is also observed in the FT–Raman spectrum of the samples upon annealing at higher temperatures. SEM images show the microstructural evolution of the powders from agglomerated nanoscaled crystallites to the nanosized pseudospherical morphology with diameter less than 50 nm. The present low temperature synthesis can be successfully applied to other oxide protonics materials highly doped with protonic defects.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Solid State Ionics - Volume 178, Issues 7–10, April 2007, Pages 569–574
نویسندگان
, , ,