Design of nanohybrid materials with dual functions

Abstract

We have successfully synthesized inorganic-inorganic, organic-inorganic and bio-inorganic nanohybrids by applying an hybridization technique systematically to layered titanate, molybdenum disulfide (MoS2), Bi-based cuprate superconductors (Bi2Sr2Cam·1Cu mOy (m = 1, 2, and 3; BSCCO)), and to layered double hydroxides (LDHs). The inorganic-inorganic systems such as TiO 2-pillared titanate, TiO2-pillared MoS2, and CdS-MoS2 hybrids were synthesized by exfoliation-reassembling method. A novel pillaring process of inorganic nanosol particles into layered compounds was developed to prepare inorganic-inorganic nanohybrids with a large surface area, high thermal stability, and enhanced photocatalytic activity. On the other hands, the organic-inorganic hybrids were achieved via intercalative complexation of iodine intercalated BSCOO with organic salt of pyridine. The high-Tc superconducting intercalate with its remarkable lattice expansion can be applied as a precursor for superconducting colloids when dispersed in an appropriate solvent. Especially, this organic-inorganic nanohybrid is expected to be a promising precursor for preparing the superconducting colloidal suspension, which could be applied to the fabrication of superconducting films or wires. Recently, we were very successful in demonstrating the formation of intercalative bio-inorganic hybrids. If necessary, LDH, as a reservoir, can be intentionally removed by dissolving it in an acidic media in such a way the interlayer biomolecules can be recovered or the intercalated biomolecules can be released from the LDH via ion-exchange reaction in electrolyte. It is, therefore, concluded that the inorganic LDH can play a role as a gene reservoir or carrier for various unstable organic or bio-molecules such as drugs and genes.