Micro-structural and thermoelectric characterization of zinc-doped In$_{0.6}$Se$_{0.4}$ crystal grown by direct vapour transport method

Crystal of zinc-doped In$_{0.6}$Se$_{0.4}$ was successfully grown by direct vapour transport (DVT) method. Grown In$_{0.6}$Se$_{0.4}$ : Zn crystal has been characterized by energy dispersive $X$-ray (EDAX) and powder $X$-ray diffractometer (XRD) techniques for compositional and micro-structural analysis, respectively. The EDAX spectra represent the grown In$_{0.6}$Se$_{0.4}$ : Zn crystal enriched with excess indium doped with Zn, which consecutively shows enhanced $n$-type conductivity. The powder XRD spectrum signified that the grown sample was crystalline and had hexagonal structure. The micro-structural parameters: average crystallite size, average lattice strain, dislocation density, and domain population were determined from powder XRD spectra. The thermoelectric properties such as Seebeck coefficient $(S)$, electrical resistivity ($\sigma^-$), and thermal conductivity $(\kappa)$ were measured in the temperature range of 313 to 368 K. Grown In$_{0.6}$Se$_{0.4}$ : Zn crystal reported Seebeck coefficient $(S)$ as high as -548 $\mu$VK$^{-1}$ and figure of merit of 1.14 at 368 K