1336-23-8Relevant articles and documents
Three new phases in the K/Cu/Th/S system: KCuThS3, K 2Cu2ThS4, and K3Cu 3Th2S7
Selby, Hugh D.,Chan, Benny C.,Hess, Ryan F.,Abney, Kent D.,Dorhout, Peter K.
, p. 6463 - 6469 (2005)
Synthetic exploration of K/Cu/Th/S quaternary phase space has yielded three new compounds: KCuThS3 (I), K2Cu2ThS 4 (II), and K3Cu3Th2S7 (III). All three phases are semiconductors with optical band gaps of 2.95, 2.17, and 2.49 eV(I-III). Compound I crystallizes in the orthorhombic space group Cmcm with a = 4.076(1) A, b = 13.864-(4) A, and c = 10.541(3) A. Compound II crystallizes in the monoclinic space group C2/m with a = 14.522(1) A, b = 4.026(3) A, and c = 7.566(6) A; β = 109.949(1)°. Compound III crystallizes in orthorhombic space group Pbcn with a = 4.051(2) A, b = 14.023(8) A, and c = 24.633(13) A. The compounds are all layered materials, with each layer composed of threads of edge-sharing ThS6 octahedra bridged by CuS4 tetrahedral threads of varying dimension. The layers are separated by well-ordered potassium ions. The relatively wide range of optical band gaps is attributed to the extent of the CuS4 motifs. As the dimension of the CuS4 chains increases, band gaps decrease in the series. All materials were characterized by single-crystal X-ray diffraction, microprobe chemical analysis, and diffuse reflectance spectroscopy (NIR-UV).
Synthesis, structure, and optical properties of K2.4Ga2.4M1.6Q8 (M = Si, Ge; Q = S, Se) crystals and glasses
He, Jianqiao,Zhang, Xian,Guo, Pan,Cheng, Ye,Zheng, Chong,Huang, Fuqiang
, p. 76789 - 76794 (2016/08/30)
Four new compounds, K2.4Ga2.4M1.6Q8 (M = Si, Ge; Q = S, Se), were successfully synthesized via a reactive flux method. All compounds crystallize in the tetragonal system of space group I4/mcm, and belong to the Tl2Se2 structure type (Pearson symbol tI16). The isostructural scaffold of the compounds feature [(Ga0.6/M0.4)Q4/2] one-dimensional chains separated by K+ ions. The chains are composed of edge-sharing [(Ga0.6/M0.4)Q4/2] tetrahedrons. Powder and glass samples were synthesized from solid state reactions with different annealing processes. The transport properties of crystalline K2.4Ga2.4Ge1.6S8 and K2.4Ga2.4Ge1.6Se8 were determined from optical absorption measurements to be wide band gap semiconductors (Eg = 3.5 eV for K2.4Ga2.4Ge1.6S8 and 2.7 eV for K2.4Ga2.4Ge1.6Se8). A red shift of the band gap energy in the glass samples was observed. K2.4Ga2.4Ge1.6S8 glass showed a wide transparent range from 0.6 μm to 10 μm and a high soften-temperature of 533 °C. First-principles calculations fitted well with the optical measurements, indicating that the Ge substitution is beneficial for narrowing the band gap.
Energetics of a zinc-sulfur fuel cell
Bendikov, Tatyana A.,Yarnitzky, Chaim,Licht, Stuart
, p. 2989 - 2995 (2007/10/03)
Energetics of a novel zinc-sulfur charge storage (generalized as Zn + S a?? ZnS) is explored to access the high (> 1000 Ah/kg) charge capacity of sulfur. At 25 ?°C, the theoretical energy density of the complete Zn/S system is a high 572 Wh/kg, at E?
