Photophysical Characterization of Ru Nanoclusters on Nanostructured TiO by Time-Resolved Photoluminescence Spectroscopy.

Despite the promising performance of Ru nanoparticles or nanoclusters on nanostructured TiO in photocatalytic and photothermal reactions, a mechanistic understanding of the photophysics is limited. The aim of this study is to uncover the nature of light-induced processes in Ru/TiO and the role of UV versus visible excitation by time-resolved photoluminescence (PL) spectroscopy. The PL at a 267 nm excitation is predominantly due to TiO, with a minor contribution of the Ru nanoclusters.

Unraveling the Mechanisms of Beneficial Cu-Doping of NiO-Based Photocathodes.

Dye-sensitized photoelectrochemical (DSPEC) water splitting is an attractive approach to convert and store solar energy into chemical bonds. However, the solar conversion efficiency of a DSPEC cell is typically low due to a poor performance of the photocathode. Here, we demonstrate that Cu-doping improves the performance of a functionalized NiO-based photocathode significantly.

Hydrogen-Generating Ru/Pt Bimetallic Photocatalysts Based on Phenyl-Phenanthroline Peripheral Ligands.

Recent studies on hydrogen-generating supramolecular bimetallic photocatalysts indicate a more important role of the peripheral ligands than expected, motivating us to design a Ru/Pt complex with 4,7-diphenyl-1,10-phenanthroline peripheral ligands. Photoinduced intra- and inter-ligand internal conversion processes have been investigated using transient absorption spectroscopy, spanning the femto- to nanosecond timescale. After photoexcitation and ultrafast intersystem crossing, triplet states localised on either the peripheral ligands or on the bridging ligand/catalytic unit are populated in a non-equilibrated way.

Methods, Mechanism, and Applications of Photodeposition in Photocatalysis: A Review.

In this review, for a variety of metals and semiconductors, an attempt is made to generalize observations in the literature on the effect of process conditions applied during photodeposition on (i) particle size distributions, (ii) oxidation states of the metals obtained, and (iii) consequences for photocatalytic activities. Process parameters include presence or absence of (organic) sacrificial agents, applied pH, presence or absence of an air/inert atmosphere, metal precursor type and concentration, and temperature. Most intensively reviewed are studies concerning (i) TiO; (ii) ZnO, focusing on Ag deposition; (iii) WO, with a strong emphasis on the photodeposition of Pt; and (iv) CdS, again with a focus on deposition of Pt.

Sorption-determined deposition of platinum on well-defined platelike WO3.

The photodeposition of Pt nanoparticles from [PtCl6 ](2-) on platelike WO3 crystals occurs preferentially on the small, subordinate facets. Rather than the often-used explanation of preferred light-induced charge migration, we propose that this phenomenon is due to differences in the intrinsic surface charges of WO3 facets exposed to water; thus, the dark sorption of [PtCl6 ](2-) on positively charged facets/edges is preferred. This conclusion is based on 1) (dark) impregnation studies, which showed Pt deposition to also be facet-specific, and 2) aqueous-phase AFM studies, which suggest intrinsic surface charges to be in agreement with sorption-based Pt distributions.