Evidence of phase heterogeneity in sol-gel Na0.5K0.5NbO3 system

0357038 - ÚACH 2011 RIV CN eng J - Článek v odborném periodiku
Chowdhury, A. - Bould, Jonathan - Londesborough, Michael Geoffrey Stephen - Večerníková, Eva - Milne, S.J.
Evidence of phase heterogeneity in sol-gel Na0.5K0.5NbO3 system.
Materials Chemistry and Physics. Roč. 124, č. 1 (2010), s. 159-162. ISSN 0254-0584. E-ISSN 1879-3312
Výzkumný záměr: CEZ:AV0Z40320502
Klíčová slova: thin films * sol-gel growth * ferroelectricity * thermal properties
Kód oboru RIV: CA - Anorganická chemie
Impakt faktor: 2.356, rok: 2010

Na0.5K0.5NbO3 thin films have been synthesised via a sol-gel route using commercially available ethoxides of sodium, potassium and niobium. X-ray diffraction confirmed that film crystallisation occurred at >= 600 degrees C, but extra peaks indicated the presence of secondary phase(s). The thin films displayed non-ferroelectric polarisation hysteresis loops. Evidence of phase heterogeneity was found from detailed analyses of the thermochemistry of the NKN precursor gels which showed multiple heating DTA exotherms for crystallisation around 480-550 degrees C. Additionally, heating DTA endotherms and cooling exotherms for NKN gels around 800-850 degrees C confirm the presence of a second phase
Trvalý link: http://hdl.handle.net/11104/0006365