High-Pressure Preparation of High-Density Cu_2ZnSnS_4 Materials

High-density Cu_2ZnSnS_4 (CZTS) materials are prepared via the mechanical alloying and high pressure sintering method using Cu_2S, ZnS and SnS_2 as the raw materials. The morphological, structural, compositional and electrical properties of the materials are investigated by using x-ray diffraction, scanning electron microscopy, and energy dispersive x-ray spectroscopy, as well as by the Raman scattering and the Hall Effect measurements. The CZTS synthesized under 5 GPa and 800^\circ\!C shows a p-type conductivity, with a resistivity of 9.69\times10^-2 \Omega \cdotcm and a carrier concentration of 1.45\times10^20 cm^-3. It is contributed to by the large grains in the materials reducing the grain boundaries, thus effectively reducing the recombination of the charge carriers.