A. Shankar

Effect of Fe-Ru doping in the electronic and thermoelectric properties of new filled skutterudite Ba(Fe,Ru)4As12

We have performed the density functional theory based calculation to study the electronic and thermoelectric properties of BaFe4−xRuxAs12 (x = 0%, 25%, 50%, 75%, and 100%) within the framework of the full potential-linearized augmented plane wave method. The composite alloys are found to be stable in their optimized crystal structures and their lattice constants are in close agreement with the corresponding experimental reports. The structural stability and mechanical properties are also studied using their elastic constants. The hardness of these materials increases with increasing concentration of Ru, which also donates the covalent nature of inter-atomic bonding of BaRu4As12. The analysis of energy bands and density of states reflects the semi-metallic nature of BaFe4As12 and BaRu4As12, whereas other doped materials show metallic character. The electronic structure calculation suggests the high Seebeck coefficient with the efficient thermoelectric application of these materials. The thermal transport i...

Electronic and optical properties of CuInTe2

The electronic and optical properties of a ternary chalcopyrite compound CuInTe2 with diamond like structure have been studied. The calculations are carried out using the density functional theory (DFT) based full potential-linearized augmented plane wave (FP- LAPW) method within the framework of GGA and modified Becke Johnson (mBJ) potential approach. The presence of direct energy band gap of 0.8 eV suggests the sample material can be a good material for solar cell application. The study of the optical response of the material against the incident photon energy radiation indicates the material can be an effective candidate for the optoelectronic devices.

Investigation of doped Perovskite systems RAIO3 using density functional theory based electronic structure and thermoelectric studies

Samarium doping effects on the thermoelectric properties in Eu1-xSmxAlO3 (x=0%, 50%, and 100%) were studied using first principles calculations based thermal transport property measurement. The result indicate that the compound is an intrinsic n-type material. Samarium doping has a positive effect on the overall thermoelectric performance of the Eu1-xSmxAlO3 system, with sharp increase in figure of merit (ZT) observed when x=0, 50 and 100% up to 150K. Compared to x=0 and 100%, the case of x=50% was found to have more positive increment in ZT value suggesting that the doing to have positive effect on figure of merit in Eu1-xSmxAlO3. Furthermore, all the samples show stable thermoelectric compatibility factors over a broad temperature range from 700 to 1000 K, which could have great benefits for their practical applications. It is concluded that the overall thermoelectric performance of the Eu1-xSmxAlO3 could be highly enhanced using doping techniques.

Study of 4f electron based compound Sm1-xGdxAlO3, a thermoelectric (TE) material: FP-LAPW method

Gadolinium doping effects on the thermoelectric properties in Sm1-xGdxAlO3 (x=0%, 50%, and 100%) were studied using first-principles calculations based thermal transport property measurement. The result indicates that the compound is an intrinsic n-type material. Samarium doping has a positive effect on the overall thermoelectric performance of the Sm1- xGdxAlO3 system, with a sharp increase in the figure of merit (ZT) observed when x=0, 25, 50, 75 and 100% up to 800K. Compared to x=0 and 100%, the case of x=50% was found to have a more positive increment in ZT value suggesting that the doping to have a positive effect on the figure of merit in Sm1-xGdxAlO3. Furthermore, all the samples show stable thermoelectric compatibility factors over a broad temperature range from 700 to 1000 K, which could have great benefits for their practical applications. It is concluded that the overall thermoelectric performance of the Sm1-xGdxAlO3 could be highly enhanced using doping techniques.