Emerging pathways in thermoelectric: Chemical bath deposition of magnesium selenide thin films for sustainable energy harvesting

Abstract

In this study, magnesium Selenide (MgSe) thin films were synthesized on glass substrate using the chemical bath deposition (CBD) method for thermoelectric power generation. After cleaning of glass substrate, selenium powder was dissolved in nitric acid to produce SeO2 and magnesium chloride was then introduced as the source of magnesium. Both SeO2 and MgCl2 were dissolved in 100 ml of dI water and later, these solutions were unified gradually. After that, the cleaned glass substrates were placed in the solution, while keeping the reaction temperature constant at 50o C for the deposition durations of 24, 48, 72, and 96 h. A number of characterization techniques, namely X-ray Diffraction (XRD), Raman spectroscopy and Scanning Electron Microscopy (SEM) were performed for structural and surface analysis of grown thin films. The effect of deposition time duration on the thermoelectric properties was investigated in depth using the Seebeck and Hall systems. It was found that the values of the Seebeck coefficient and power factor obey the increasing trend with maximum values 196.93 μV/K and 21.5 × 10−8 W/mK2 respectively. These observed values are seems to be the highest values for magnesium selenide thin film ever reported in the literature according to the best of our knowledge. Therefore, we have concluded that MgSe thin films supposed to be emerging material for thermoelectric power generation applications.