Synthesis and electrical property of tin double oxides with tunnel framework

首先，我们制备了具有开放骨架的新型锡双氧化物。C.Keller和A.R.West报道了Li_2MgSn3O_8的晶体结构。(J.Mater.SCI。Let.，2(1983)451-452)Li_2MgSn3O_8是由SnO_6和MgO_6组成的骨架，Li~(2+)离子位于1×2隧道中。我们尝试用更大的碱离子K^+、Rb^+或Cs^+代替Li^+来合成具有更大隧道的新型锡氧化物，例如2×2或3×3。作为结果，我们成功地制备了A_xMG_&lt；x/2&gt；Sn_&lt；8-x/2&gt；O_&lt；16&gt；(x≦2)(K，Rb和Cs)和K_xCa_&lt；x/2&gt；Snt_&lt；8-x/2&gt；O_&lt；16&gt；(x≦2)。O_&lt；16&gt；(x≦_2)(K，Rb和Cs)和K_xCa_&lt；x/2&gt；Sn_&lt；8-x/2&gt；O_&lt；16&gt；(x≦2)有望具有优良的离子和电子电导性能。为了研究这两种化合物的电学性质，我们研究了它们晶体的助熔剂生长。用过量的K_2CO_3作助熔剂制备了多晶K_xCa_&lt；x/2&gt；Snt_&lt；8-x/2&gt；O_&lt；16&gt；(x≦_2)。该多晶是由K_xCa_&lt；x/2&gt；Snt_&lt；8-x/2&gt；O_&lt；16&gt；(x≦2)纤维单晶捆扎成束而成。其尺寸(M3)为1.5 mm×0.2 mm×0.2 mm。经电导率测定，K_xCa_&lt；x/2&gt；Sn_&lt；8-x/2&gt；O_&lt；16&gt；(x≦2)的电导率为σ_&lt；300&gt；-2×10^&lt；-9；Ω^&lt；-1；结果表明，一维沟道中的主要载流子是钾离子。结果表明，两种新的荷兰锡氧化物：A_xMG_&lt；x/2&gt；Snt_&lt；8-x/2&gt；O_&lt；16&gt；(K，Rb，Cs)和K_xCa_&lt；x/2&gt；Snt&lt；8-x/2&gt；O_&lt；16&gt；(X≦2)将用于电解液，特别是用于

First, we have prepared new tin double oxides with open framework. C.Keller and A.R.West had reported Li_2MgSn_3O_8 with a ramsdellite structure. (J.Mater. Sci. Lett., 2 (1983) 451-452) The framework of Li_2MgSn_3O_8 is constructed by SnO_6 and MgO_6 Li^+ ions are located in 1×2 tunnel. We have tried to synthesize new tin double oxides with larger tunnels, for example 2×2 or 3×3, by using lager alkali ions, K^+, Rb^+, or Cs^+ instead of Li^+ ion. As a restult, we succeeded in preparing A_xMg_<x/2>Sn_<8-x/2>O_<16> (x≦2)(K, Rb and Cs) and K_xCa_<x/2>Sn_<8-x/2>O_<16> (x≦2) with a hollandite structure.Both A_xMg_<x/2>Sn_<8-x/2>O_<16> (x≦2)(K, Rb and Cs) and K_xCa_<x/2>Sn_<8-x/2>O_<16> (x≦2) were expected that they would have excellent ion and electron conductivities. In order to investigate electrical properties of both compounds, we have studied the flux growth of their crystals. Polycrystalline K_xCa_<x/2>Sn_<8-x/2>O_<16> (x≦2) was obtained by using excess K_2CO_3 as flux. The polycrystal was made by tying fibrous single crystals of K_xCa_<x/2>Sn_<8-x/2>O_<16> (x≦2) in a bundle. Its size (mm_3) was 1.5 mm×0.2 mm×0.2 mm. After conductivity measurement, the conductivity of K_xCa_<x/2>Sn_<8-x/2>O_<16> (x≦2) was σ_<300>=2.2×10^<-9>Ω^<-1> m^<-1> at room temperature, and the activation energy was calculated to be 0.63eV.The result suggested that the chief charge carrier is potassium ion in 1D channels.In conclusion, it is expected that both new hollandite tin double oxides, A_xMg_<x/2>Sn_<8-x/2>O_<16> (K, Rb, and Cs) and K_xCa_<x/2>Sn_<8-x/2>O_<16> (x≦2) will be applied to electrolytes, especially to