K_4Sn_3Se_8的固相合成、晶体结构和反射光谱研究

Solid state synthesis,crystal structure and diffuse reflectance spectra of K_4Sn_3Se_8

采用反应性熔盐法 ,通过中温固相反应在 5 0 0℃下合成晶体K4Sn3 Se8。该晶体属正交晶系 ,空间群Ccca ,晶胞参数 :a =0 82 115 (6 )nm ,b =2 7790 (2 )nm ,c =0 8186 5 (6 )nm ,V =1 86 82 (2 )nm3 ,Z =4。K4Sn3 Se8由[Sn3 Se8]4 三聚体负离子和K+ 正离子组成。漫反射光谱研究表明该材料能隙 (Eg)为 2 6eV ,属于半导体 ,对太阳能具有选择吸收的特性。

A ternary metal selenide K_4Sn_3Se_8 was synthesized by use of the reactive molten salt method at 500?℃. The orange red granular crystals crystallized in orthorhombic space group Ccca with cell parameters: a =0.821?15(6)?nm, b =2.779?0(2)?nm, c =0.818?65(6)?nm, V =1.868?2(2)?nm 3 and Z =4. K_4Sn_3Se_8 has a zero-dimensional structure consisting of 4- trimeric anions and K+ cations. Diffuse reflective spectra of the powder sample indicated that this compound is a semiconductor with an energy gape of 2.6?eV.