Growth of large size SnSe crystal via directional solidification and evaluation of its properties

SnSe crystal is an attractive Ⅳ-Ⅵ thermoelectric (TE) material. In this work, a Ø25 × 50 mm3 SnSe crystal was prepared using a directional solidification method. The as-grown crystal has standard Pnma structure at room temperature. The band gap Eg is determined to be 0.96 eV which agrees well with the theoretical value. Thermal expansion measurements show that SnSe crystal has significant anisotropic expansion behaviors. The linear thermal...