Summary: | This study was focused on enhancing the conductivity of lithium tin phosphate, LiSn2P3O12 by partially substituting Sn4+ ions with Cr3+ ions to obtain system with general formula Li1+xCrxSn2-xP3O12. Li1+xCrxSn2-xP3O12 powders with x = 0.2, 0.4, 0.6 and 0.8 were prepared by mechanochemical milling method. X-ray diffraction analysis indicated that all samples consisted of triclinic crystalline LiSn2P3O12 structure. Energy Dispersive X-ray analysis suggested that Cr3+ was successfully substituted into the LiSn2P3O12 crystalline structure. Impedance analysis showed an increase in conductivity with increase in x. The enhancement in bulk conductivity was due to increase in number and polarisability of Li+ ions and crystallinity. The increase in grain boundary conductivity was ascribed to enhancement in Li+ migration as a result of increase in contact between grains. The conductivity versus the reciprocal of temperature plots showed a sudden change in conductivity at 393 K for the sample with x = 0.2 and 373 K for the sample with x = 0.4, 0.6 and 0.8. This was attributed to a structure transitionphenomenon. All samples showed Arrhenian behaviour.© 2012 by ESG.
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