ExperimentalTetraethoxysilane (TEOS), nitric acid, surfactant, and 2,5-diiodothiophene were mixed in tetrahydrofuran (THF) at room temperature for half an hour to form a precursor solution. The catalytic complex was formed by reacting palladium acetate, cuprous iodide, and triphenylphosphine (PPh 3 ) in THF. A typical synthesis utilizes a molar ratio of reactants of THF/HNO 3 /TEOS/Brij-58/PPh 3 / CuI/Pd(OAc) 2 /2,5-diiodothiophene of 6.2:0.356:0.937:0.1:0.04:0.014:0.017:0.1, where Brij-58 is a non-ionic surfactant CH 3 (CH 2 ) 15 (OCH 2 CH 2 ) 20 OH. Films were prepared by either spin-coating the mixture of the catalytic complex and precursor solutions onto glass slides using a Specialty Coating Systems P-6000 spin-coater or allowing them to evaporate in a petri dish to form xerogels. The thin films were exposed to acetylene gas and triethylamine vapor at room temperature and 50 psi pressure for up to 3 days to polymerize the incorporated monomer. Pure conjugated PTE was obtained by washing with dilute HF to remove the silica and by ethanol extraction to remove the surfactant. The PTE was washed with ethanol to remove the unbound catalyst and partially dissolved in chloroform to achieve oligomeric PTE solutions that were subsequently coated on glass slides to form red oligomeric PTE films. The oligomeric PTE films were exposed to acetylene gas and the continuous reactions of acetylene with the active complex attached to the oligomers resulted in darkened films with increased UV-vis absorptions.The nanocomposites were characterized by transmission electron microscope (TEM, JEOL 2010, operated at 200 kV), X-ray diffraction (XRD, Phillips Xpert X-ray diffractometer using Cu Ka radiation at k = 0.1542 nm), UV-vis spectroscopy (Beckman DU460B UV-vis), Fourier transform infrared spectroscopy (FTIR, Thermo Nicolet Nexus 670 spectrophotometer with a Smart MIRacle horizontal attenuated total reflectance Ge crystal accessory), and by differential thermal analysis and thermogravimetric analysis (DTA/TGA, 2960 Simultaneous DTA±TGA by TA Instruments) operated at 10 C min ±1 from 30 to 1200 C with argon sweep gas.

Quasi-ordered, highly dispersed, gold nanoclusters of tightly controlled particle size were synthesized by dip-coating substrates with gold precursors encapsulated by block-copolymer micelles. By this method, gold particles (4.8 +/- 1.3 nm) were deposited on ITO-coated glass and shown to be catalytically active for electro-oxidation of carbon monoxide. XPS confirmed the catalytically active particles were predominantly Au0; however, a large fraction existed as Au3+. Whereas bulk gold is inert, these results demonstrate that catalytically active Au nanoparticles can be derived from micelle encapsulation.

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Supported Au nanoclusters synthesized from diblock copolymer micelles can be reliably prepared with well-controlled sizes and dispersions. For particles with diameters between approximately 1 and 6 nm, the particle size and the support were found to strongly influence the oxygen reactivity, the formation and stabilization of a metal-oxide, and the catalytic activity for electrooxidation of carbon monoxide. The smallest particles studied (1.5 nm) were the most active for electrooxidation of CO and had the largest fraction of oxygen associated with gold at the surface as measured by the Au(3+)/Au(0) X-ray photoemission intensities. Conducting and semiconducting substrates, ITO-coated glass and TiO(2), respectively, were associated with greater stabilization of Au(3+) oxide as compared to insulating, SiO(2), substrates.

Nanoparticulate tungsten oxide films were synthesized by pulsed electrodeposition. Particle sizes between 45 and ∼330 nm were achieved by varying pulse duration from 5 to 500 ms. Shorter pulses increased the rate of new particle nucleation above the rate of existing particle growth, allowing for the observed variations in size. Cathodic deposition voltage (−1 ∼ −3 V) had little effect on particle size. Compared to films prepared by continuous electrodeposition, nanoparticulate tungsten oxide films showed a higher photoactivity and greater current density for the hydrogen intercalation reaction. Functional improvements are explained by the smaller particle size and larger surface area of nanocrystalline tungsten oxide.