A systematic study on the influence of Nd^(3+) substitution on structural,magnetic and electrical properties of cobalt ferrite nanopowders obtained by sol–gel auto-combustion routewas reported.The formation of spinel...A systematic study on the influence of Nd^(3+) substitution on structural,magnetic and electrical properties of cobalt ferrite nanopowders obtained by sol–gel auto-combustion routewas reported.The formation of spinel phasewas confirmed by X-ray diffraction(XRD)data,and percolation limit ofNd3?into the spinel lattice was also observed.Fourier transform infrared spectroscopy(FTIR)bands observed ≈580 and ≈390 cm^(-1 ) support the presence of Fe^(3+) at A andBsites in the spinel lattice.The variation in microstructure was investigated by scanning electronmicroscopy(SEM),and the average grain size varies from 5.3 to 3.3 lm.The substitution of Nd^(3+) significantly affects the formation of pores and grain size of cobalt ferrite.Room-temperature saturation magnetization and coercivity decrease from 60 to 30 mA·m^(2)·g^(-1) and 19.9–17.8 mT,respectively,with Nd^(3+) substitution increasing.These decreases in magnetic properties are explained based on the presence of non-magnetic nature of Nd^(3+) concentration and the dilution of super-exchange interaction in the spinel lattice.The room-temperature direct-current electrical resistivity increases with Nd^(3+) concentration increasing,which is due to the unavailability of Fe^(2+) at octahedral B sites.展开更多
基金Authors would like to thank the management of Koneru Lakshmaiah Education Foundation for giving us the support and encouragement to do research.RAR,GKK,NKJ would like to thank Department of Science and Technology(DST),Govt.of India,for the award of DST-FIST Level-1(SR/FST/PS-1/2018/35)scheme to Department of Physics,KLEF.
文摘A systematic study on the influence of Nd^(3+) substitution on structural,magnetic and electrical properties of cobalt ferrite nanopowders obtained by sol–gel auto-combustion routewas reported.The formation of spinel phasewas confirmed by X-ray diffraction(XRD)data,and percolation limit ofNd3?into the spinel lattice was also observed.Fourier transform infrared spectroscopy(FTIR)bands observed ≈580 and ≈390 cm^(-1 ) support the presence of Fe^(3+) at A andBsites in the spinel lattice.The variation in microstructure was investigated by scanning electronmicroscopy(SEM),and the average grain size varies from 5.3 to 3.3 lm.The substitution of Nd^(3+) significantly affects the formation of pores and grain size of cobalt ferrite.Room-temperature saturation magnetization and coercivity decrease from 60 to 30 mA·m^(2)·g^(-1) and 19.9–17.8 mT,respectively,with Nd^(3+) substitution increasing.These decreases in magnetic properties are explained based on the presence of non-magnetic nature of Nd^(3+) concentration and the dilution of super-exchange interaction in the spinel lattice.The room-temperature direct-current electrical resistivity increases with Nd^(3+) concentration increasing,which is due to the unavailability of Fe^(2+) at octahedral B sites.
