Investigating the novel thermoelectric properties of magnesium, calcium, and barium divanadate oxides (XV2O6 where X = Mg, Ca, and Ba) for waste heat recovery applications in energy harvesting devices

In this study, the unique thermoelectric properties along with structural, electronic, and photoluminescence properties of divanadate oxides XV 2 O 6 (X = Mg, Ca, and Ba) have been investigated using DFT and experimental routes for waste heat recovery applications. For the synthesis process, the solid-state reaction technique was employed and the monoclinic structure of the synthesized oxides was confirmed by the XRD results. The formation of well-shaped particles was demonstrated by SEM images and the presence of Mg, Ca, Ba, V, and O with the proper compositions was confirmed by EDS mapping. The calculated bandgap values for MgV 2 O 6 , CaV 2 O 6 , and BaV 2 O 6 were 3.20 eV, 2.14 eV, and 1.76 eV, respectively. To see how atomic orbitals affect the creation of bands, total and partial density of states calculations were also made. The BoltzTraP algorithm within Wien2k was used to study transport properties. Photoluminescence (PL) was done to analyze the optical behavior of synthesized oxides. For all the divanadate oxides XV 2 O 6 (X = Mg, Ca, Ba), productive values for the Seebeck coefficient (S), electrical conductivity (σ), power factor (PF), and figure of merit (ZT) have been observed. The semi-metallic nature, low synthesis cost, and thermoelectric results demonstrate that the studied oxides have exceptional potential for waste heat recovery applications and can be very efficient in energy harvesting devices, especially in thermoelectric generators.