Structural and thermoelectric properties of pure and La, Y doped HoMnO3 for their use as alternative energy materials

HoMnO3 and its La and Y doped compounds Ho0.67La0.33MnO3 and Ho0.67Y0.33MnO3 are investigated for their structural and thermoelectric transport properties. Small bandgaps of these compounds, as investigated by first principles calculations, make them suitable for application in thermoelectric devices. It is found that the bandgap of pure HoMnO3 increases with La and Y dopants. Thermoelectric parameters such as Seebeck coefficient, electric conductivity and thermal conductivity are calculated and their dependences on chemical potential are reported. Electrical conductivity is found to be of the order of 10(20) 1/m Omega s, and thermal conductivity of the order of 10(15) W/mKs for all these alloys. HoMnO3 in pure form and in the presence of La and Y dopants is very suitable for thermoelectric devices and as alternative energy materials. (C) 2014 Elsevier B.V. All rights reserved.