Thermoelectric properties of LaFe₃CoSb₁₂ skutterudite materials with different nanostructures

【摘要】 Nanostructures with different morphologies could profoundly influence the electron and phonon transport in thermoelectric materials and thus their properties could be improved by tuning the nanostructures.The LaFe3CoSb12 skutterudite nano powders with differentmorphologies were fabricated via a hydro/solvo thermal route.The microstructures of the hot-pressed LaFe3CoSb12 bulks were characterizedthrough X-ray diffraction(XRD) and scanning electron microscopy(SEM) and the effects of the nanostructures on the thermoelectric properties were investigated by measuring the electrical conductivity,the Seebeck coefficient and the thermal conductivity.The results suggestedthat the mixed morphology of nanorods and nanospheres could enhance the electrical conductivity largely although the Seebeck coefficientwas decreased and the thermal conductivity was increased slightly.Differently,a higher Seebeck coefficient,a lower thermal conductivity anda lower electrical conductivity could be obtained for the LaFe3CoSb12 bulk with a single morphology of nanospheres.Consequently,the figure of merit of LaFe3CoSb12 bulk with a mixed morphology of nanorods and nanospheres could be increased by about 59% as compared tothat with a single morphology of nanospheres.更多还原

【Abstract】 Nanostructures with different morphologies could profoundly influence the electron and phonon transport in thermoelectric materials and thus their properties could be improved by tuning the nanostructures.The LaFe3CoSb12 skutterudite nano powders with differentmorphologies were fabricated via a hydro/solvo thermal route.The microstructures of the hot-pressed LaFe3CoSb12 bulks were characterizedthrough X-ray diffraction(XRD) and scanning electron microscopy(SEM) and the effects of the nanostructures on the thermoelectric properties were investigated by measuring the electrical conductivity,the Seebeck coefficient and the thermal conductivity.The results suggestedthat the mixed morphology of nanorods and nanospheres could enhance the electrical conductivity largely although the Seebeck coefficientwas decreased and the thermal conductivity was increased slightly.Differently,a higher Seebeck coefficient,a lower thermal conductivity anda lower electrical conductivity could be obtained for the LaFe3CoSb12 bulk with a single morphology of nanospheres.Consequently,the figure of merit of LaFe3CoSb12 bulk with a mixed morphology of nanorods and nanospheres could be increased by about 59% as compared tothat with a single morphology of nanospheres.更多还原