2001 heterogeneous catalysis, catalysts

heterogeneous catalysis, catalystsH 2000

22 - 013Semiconductor–Metal Nanocomposites. Photoinduced Fusion andPhotocatalysis of Gold-Capped TiO2 (TiO2/Gold) Nanoparticles. —Au-capped TiO2 nanoparticles are prepared by addition of a HAuCl4 solutionto a colloidal TiO2 suspension in water followed by reduction of AuCl4− withNaBH4. The particles are characterized by absorption spectroscopy and TEM.The concentration of the TiO2 core directly influences the particle size and thestability of the composite nanoparticles. Aggregation effects are observed fornanoparticles with a TiO2:Au ratio less than 1:1. Laser pulse excitation of theseaggregated nanoparticles results in fusion and formation of larger particles.The Au/TiO2 nanoparticles show good photocatalytic properties. More than40% enhancement in the efficiency of thiocyanate oxidation is achieved. —(DAWSON, AMY; KAMAT, PRASHANT V.; J. Phys. Chem. B 105 (2001) 5,960-966; Radiat. Lab., Univ. Notre Dame, Notre Dame, IN 46556, USA; EN)

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