Structural, Thermal and Electrical Conduction Studies on LiNiPO4: RE (RE= La, Nd) Prepared by Polyol Method
LiNiPO4 and LiNiPO4: xRE (RE = La, Nd) (x = 0.01 mol%, 0.03 mol%, 0.05 mol%, 0.07 mol%, 0.09 mol%) samples have been prepared by polyol method using 1, 2 propanediol as a polyol medium. XRD patterns have indicated that the pristine LiNiPO4 is well crystallized with orthorhombic structure pnma space group and structurally stable compound upon doping of rare earth metals. Functional group analyses have been carried out by FTIR spectroscopic analysis. TG analysis shows that no weight loss has been observed above 600°C for both Nd3+ and La3+ doped LiNiPO4. The morphology of the samples was analyzed through Scanning Electron Microscopy. The conductivity of LiNiPO4 was found to be improved by 2 orders by doping of rare earth ions. It is found that lanthanum is an excellent dopant for LiNiPO4 than neodymium due to the formation of free ion sites which causes the enhancement of conductivity. Dielectric studies support that doping of La3+ is favorable for conduction compared with Nd3+ doping.
LiNiPO4, Li-ion battery, electrical conductivity, dielectric properties
The financial support from BRNS, Government of India, DAE, research project 2010/20/37P/3/BRNS/1062 is gratefully acknowledged.One of the authors (S.Karthickprabhu) thanks the BRNS, DAE, Government of India, for the award of Junior Research Fellowship.
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