Synthesis of Sr_(1+2x)La_(1-2x)Fe_(1-x)NbxO4(x=0,0.1,0.3,and 0.5)by Sol-gel Method: Structural,Magnetic,and Dielectric Properties

摘要

One-layered Ruddlesden-Popper phase Sr_(1+2x)La_(1-2x)Fe_(1-x)NbxO4 doped with niobium was synthesized using a sol-gel method for various Nb concentrations(x=0,0.1,0.3,and 0.5).Singlephase samples could be observed with x=0 and 0.1,while x= 0.3 and 0.5 contain additional phases.Microstructure results showed that the increase of niobium content corresponded to a decrease in the grain size of the samples.The magnetic measurements indicated that antiferromagnetic interactions of doped samples had decreased.The dielectric constant of the samples decreased as x increased due to the increase in conductivity.The origin of conduction in the samples might be caused by hopping conduction due to the mixed oxidation states of iron with charge +3 and +4.