CdS MINERALIZATION OF HEXAGONAL, LAMELLAR, AND CUBIC LYOTROPIC LIQUID CRYSTALS

نویسندگان

  • Paul V. Braun
  • Samuel I. Stupp
چکیده

Growth of CdS was studied in three different liquid crystalline phases demonstrating the versatility of liquid crystal templating of inorganic solids. Semiconductor growth in a hexagonal liquid crystal yielded a nanostructure with hexagonal symmetry, a lamellar liquid crystal yielded a lamellar nanostructure, and a cubic liquid crystal (consisting of spherical micelles) yielded a hollow, spherical product. The product grown in the hexagonal liquid crystal contains rod-like pores of 3 nm diameter, spaced 8 nm apart in a hexagonal lattice. The product grown in the lamellar liquid crystal consists of CdS sheets 5 nm thick, with 2 nm spaces between layers, which presumably contain the organic template. Both these superlattices have virtually identical symmetries and characteristic dimensions as the liquid crystal in which they were formed. The mineralization of the cubic phase yielded hollow spheres of CdS, 20–100 nm in diameter, 1–5 times the diameter of the micelles making up the liquid crystal. © 1999 Elsevier Science Ltd

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تاریخ انتشار 2001