Abstract
Decomposition temperatures of LnMn 2O 5 (Ln = Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Y) were measured by thermogravimetry (TG) and differential thermal analysis under various oxygen partial pressures P O 2 = 10 −4−1 atm. The decomposition reactions were confirmed by identifying the decomposition products with powder X-ray diffractometry and determining weight loss from TG as follows. LnMn 2O 5 → LnMnO 3 + 1 3 Mn 3O 4 + 1 3 O 2 Among LnMn 2O 5 phases the most stable phases are GdMn 2O 5 and DyMn 2O 5, while the most unstable phase is PrMn 2O 5. The Gibbs free energy, enthalpy and entropy changes of the decomposition reactions for LnMn 2O 5 phase were determined from the oxygen partial pressure at the decomposition temperature. The standard enthalpies and entropies of formation of LnMn 2O 5 were estimated
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
