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Synthesis and crystallization of lead-zirconium-titanate (PZT) nanotubes at the low temperature using carbon nanotubes (CNTs) as sacrificial templates
, Article Advanced Powder Technology ; Volume 23, Issue 5 , September , 2012 , Pages 647-654 ; 09218831 (ISSN) ; Tabei, S. A ; Nemati, A ; Eder, D ; Pradeep, T ; Sharif University of Technology
Elsevier
2012
Abstract
Pb(Zr 0.52Ti 0.48)O 3 (PZT) nanotubes with diameters of 80-100 nm and a wall thickness of 15-20 nm were prepared by sol-gel template technique and using multi-walled carbon nanotubes (MWCNT) as sacrificial templates. The coating process of MWCNT with PZT precursor sol and removal of the carbon nanotubes by an interrupt heat treatment were discussed and studied by Raman spectroscopy. Simultaneous thermal analysis (STA) revealed that PZT nanotube crystallized at the low temperature of 410°C by the significantly low activation energy of crystallization of 103.7 kJ/mol. Moreover, based on the X-ray diffraction (XRD) pattern and selected area electron diffraction pattern the crystal structure of...
Synthesis and characterisation of nanostructured neodymium titanium oxides by sol-gel process: Controlling the phase composition, crystal structure and grain size
, Article Materials Chemistry and Physics ; Volume 122, Issue 2-3 , 2010 , Pages 512-523 ; 02540584 (ISSN) ; Fray, D. J ; Sharif University of Technology
2010
Abstract
Nanocrystalline neodymium titanium oxide thin films and powders with different phase compositions with mesoporous structure were produced by a straightforward particulate sol-gel route. The sols were prepared in various Nd:Ti molar ratios and they showed a narrow particle size distribution in the range 20-26 nm. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) revealed that the powders contained mixtures of Nd4Ti9O24, Nd2Ti4O11, Nd3Ti4O12 for titanium dominant powders (Nd:Ti ≤ 45:60), mixtures of Nd2TiO5 and Nd2O3 for neodymium dominant powders (Nd:Ti ≥ 75:25) and pure Nd3Ti4O12 phase for equal molar ratio of Nd:Ti, depending on the annealing temperature and Nd:Ti...