Abstract:

Nanoparticles (1-6 nm) of transition metals (e.g., Pt, Pd), alloys, metal oxides (e.g., FeOOH, SiO2), and ceramics are prepd. by chem. reaction under mild conditions using precursor solns. of complex liqs. (e.g., microemulsions, liq. crystals) contg. surfactants and alkoxides. The resulting nanoparticles are dispersed in polymer solns. as fine colloids, and used to form transparent nanoparticle-contg. plastic films. The water is non freezing, the mild conditions are atm. pressure and a temp. range of room temp. to 70°C, and the reaction is selected among a hydrolysis, redn. and exchange process. In an example, a Pd colloidal dispersion was prepd. from a soln. contg. K2PdCl4, Aliquat 336, dichloroethane and water, which was reacted with NaHCO2 under Ar at 75°C for 1 h. The solvent was evapd. off, leaving a waxy residue which was washed and dried. The Pd nanoparticles were redispersed in polyvinylalc., and used for forming a transparent film coating on a glass plate. [on SciFinder(R)]