Abstract
CuFeSe2 powder materials were prepared by hydrothermal method using raw materials of copper chloride, ferric chloride and selenium dioxide. The effects of different heat treatment temperature and time on the phase formation of CuFeSe2 were investigated. The experimental results show that, CuFeSe2 crystals start to form when the heat treatment is performed at 180 °C for 2 h and 40 h respectively, and when the temperature reaches 200 °C, the X-ray diffraction (XRD) peak of CuFeSe2 becomes higher, which indicates that the crystallinity of CuFeSe2 crystal is better. The target product CuFeSe2 crystals can be found at 180 °C for 30 h and 40 h respectively, and the longer the time, the stronger the XRD peak for CuFeSe2 crystal. CuFeSe2 crystals are formed when the heat treatment time is 5 h to 40 h at 200 °C. When the reaction time is 5 h and 20 h at 200 °C, the product CuFeSe2 powder is less than 100 nm in size and consists of large polygonal crystals and smaller oval grains; When the reaction time is 20 h, 30 h at 160 °C, the product CuFeSe2 powder composed of uneven grains and there is agglomeration among the grains.