Growth and characterization of SnS_2(1-x)Se_2x alloys

In this study, SnS_2(1-x)Se_2x alloys layered crystals were grown by the chemical vapor transport method. The crystal structure characterization has been substantiated by X-ray diffraction (XRD) and transmission electron microscope technologies. From each sample's XRD pattern, the peaks corresponds to (001), (002), (003), (004), and (005) which were found and used to determine the lattice constants. The band gap energies modulated from 2.28 eV (SnS₂) to 1.23 eV (SnSe₂) with the increasing content of Se, which were verified by piezoreflectance (PzR) spectra and absorption spectra. By PzR spectra and absorption spectra, the empirical relation between band gap energies and composition ratio, according to the extended Vegard's law, has been predicted; accorded with a bowing parameter b of 0.56 and 0.54 eV, respectively.