Synthesis, Crystal Structure, and Optical Properties of Noncentrosymmetric Na2ZnSnS4
Synthesis, Crystal Structure, and Optical Properties of Noncentrosymmetric Na2ZnSnS4
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DOI：
10.1021/acs.inorgchem.8b01025
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发表时间：
2018-08-20
影响因子：
4.6
通讯作者：
Huang, Fuqiang
中科院分区：
文献类型：
--
作者：
He, Jianqiao;Guo, Yangwu;Huang, Fuqiang
以Na_2S_2为助熔剂，成功地合成了一种新的硫属化合物Na_2ZnSnS_4。Na_2ZnSnS_4晶体属于四方晶系，空间群为I（4），在bar上。其晶胞参数为a = 6.4835（6）埃，c = 9.134（1）埃。该结构是AgGaS 2的衍生物，其中Ag+离子被Na+离子取代，Ga 3+离子被Zn 2+和Sn'离子取代。所有三种阳离子都是严重扭曲的四面体几何形状，扭曲因子（eta = c/a）为1.4。光学测量表明，Na 2 ZnSnS 4粉末样品具有从0.8到25 μ m的大的透明范围和3.1eV的宽带隙。在41 - 74 μ m的晶粒尺寸范围内，它具有0.9 × AgGaS 2的大的二次谐波产生强度。第一性原理计算结果表明，价带顶和导带底分别主要由S 3 p，Zn 3d轨道和Sn Ss，S 3 p轨道组成.
A new chalcogenide Na2ZnSnS4 has been successfully synthesized by using Na2S2 as reactive flux. Na2ZnSnS4 crystallizes in the tetragonal system with space group of I (4) over bar. Its cell parameters are a = 6.4835(6) angstrom and c = 9.134(1) angstrom. The structure is a derivative of AgGaS2, in which the Ag+ ions are replaced by Na+ ions and the Ga3+ ions are replaced by Zn2+ and Sn' ions. All three cations are in seriously distorted tetrahedral geometry with a distortion factor (eta = c/a) of 1.4. Optical measurements show that the Na2ZnSnS4 powder sample has a large transparent range from 0.8 to 25 ym and a wide band gap of 3.1 eV. It exhibits large second harmonic generation intensity of 0.9 x AgGaS2 in the grain size range from 41 to 74 ym. First-principles calculation results reveal that the valence band maximum and conduction band minimum are mainly composed of S 3p, Zn 3d orbitals and Sn Ss, S 3p orbitals, respectively.