The mechanism of plasmon-induced charge separation of gold nanoparticles (Au NPs) on TiO2 was investigated with the help of anionic ligands. Au NPs are oxidized in the presence of KX (X = SCN, Br or Cl), chiefly via direct oxidation to [AuX4](-). The reactivity of Au NPs depends on the solution pH, the type of anion ligands and the excitation wavelength, suggesting that the photopotential of Au...

The growth of Au on an ultra-thin, ordered Mo(112)–(8 · 2)-TiOx, was investigated using scanning tunneling microscopy (STM), low energy ion scattering spectroscopy (LEISS), X-ray photoelectron spectroscopy (XPS), and temperature programmed desorption (TPD). Wetting of the TiOx surface by Au was observed with STM and LEISS, and the ordering of the Au films was atomically resolved with STM. TPD s...

The well controlled fabrication of supported bimetallic nanoparticles has inspired material scientists in the design of new methodologies [1]. This study presents a systematic approach for the synthesis, characterization (TEM, XPS, XRD, UV-Vis), and evaluation of bimetallic nanoparticles Pd-Au supported on Titania-P90 which are highly active and selective in photocatalytic oxidation of methanol...

Integrating plasmon resonant nanostructures with photocatalytic semiconductors shows great promise for high efficiency photocatalytic water splitting. However, the electrochemical instability of most III-V semiconductors severely limits their applicability in photocatalysis. In this work, we passivate p-type GaP with a thin layer of n-type TiO2 using atomic layer deposition. The TiO2 passivatio...

Although the early publications by Bond et al. [1,2] and Parravano et al. [3,4] reported that small gold particles exhibited catalytic activity for some reactions, such as hydrogenation of olefins and oxygen transfer reactions, gold was generally considered to be catalytically inactive [5]. Over the past 20 years, the volume of literature on the application of gold catalysts has been steadily i...

The interaction of Au with oxide supports has been found to play a vital role in determining the unique properties of Au catalysts. In this study, the binding of Au with titania was investigated using scanning tunneling microscopy (STM) and ultra-violet photoemission spectroscopy (UPS). Two support systems, rutile TiO2(110) and an ordered TiOx/Mo(112) thin film were used. On a highly defective ...

Atomic hydrogen adsorption energies on bimetallic overlayer systems have been determined by periodic density functional theory calculations within the generalized gradient approximation. On the pseudomorphic Pd/Cu(111) surface, both the substrate interaction and the lattice compression of the Pd overlayer lead to smaller hydrogen binding energies. For pseudomorphic Cu/Pd(111), on the hand, the ...

This article explains the mechanism of the metal/oxide core-shell Ag/TiO2 and Au/TiO2 nanoparticle formation via one-step ultrasonic spray pyrolysis (USP) by establishing a new model. The general knowledge on the standard “droplet-to-particle” (DTP) mechanism, nucleation, and growth processes of noble metals, as well as physical and chemical properties of core and shell materials and experiment...

Growth mechanism of chemically-driven RuO2 nanowires is explored and used to fabricate three-dimensional RuO2 branched Au-TiO2 nanowire electrodes for the photostable solar water oxidation. For the real time structural evolution during the nanowire growth, the amorphous RuO2 precursors (Ru(OH)3 · H2O) are heated at 180 (°)C, producing the RuO2 nanoparticles with the tetragonal crystallographic ...

Despite the rising technological interest in the use of calcium-modified TiO2 surfaces in biomedical implants, the Ca/TiO2 interface has not been studied in an aqueous environment. This investigation is the first report on the use of in situ scanning tunneling microscopy (STM) to study calcium-modified rutile TiO2(110) surfaces immersed in high purity water. The TiO2 surface was prepared under ...