Formic Acid Photo-Fuel Cells Consisting of TiO Photoanode and Pt Cathode.

Formic acid (HCOOH) has attracted much attention as a promising power source for portable electronic devices because of its ease of storage and transportation. Here we report that a simple HCOOH photo-fuel cell (PFC) consisting of mesoporous anatase TiO photoanode and Pt cathode stably delivers a short-circuit photocurrent (J) of 5.94 mA cm and an open-circuit voltage of 0.

Efficient plasmonic water splitting by heteroepitaxial junction-induced faceting of gold nanoparticles on an anatase titanium(IV) oxide nanoplate array electrode.

Plasmonic photocatalysts represented by gold nanoparticle (NP)-loaded titanium(IV) oxide (Au/TiO) can be promising solar-to-fuel converters by virtue of their response to visible-to-near infrared light. Hitherto, Au/rutile (R)-TiO has been recognized as exhibiting photocatalytic activity higher than that of Au/anatase (A)-TiO. Herein, we demonstrate that the high potential of A-TiO as the Au NP support can be brought out through atomic level interface control.

Crystallographic interface control of the plasmonic photocatalyst consisting of gold nanoparticles and titanium(iv) oxide.

A big question in the field of plasmonic photocatalysis is why a typical photocatalyst consisting of gold nanoparticles and rutile titanium(iv) oxide (Au/R-TiO) usually exhibits activity much higher than that of Au/anatase TiO (Au/A-TiO) under visible-light irradiation. Shedding light on the origin should present important guidelines for the material design of plasmonic photocatalysts. Au nanoparticles (NPs) were loaded on ordinary irregular-shaped TiO particles by the conventional deposition precipitation method.

Bottom-up formation of gold truncated pyramids smaller than 10 nm on SrTiO nanocubes: an application for plasmonic water oxidation.

An atomically commensurate interface gives rise to Au truncated pyramids < 10 nm on single-crystalline SrTiO nanocubes (NCs) in a simple deposition-precipitation process without a surface modifier, and the resulting hybrid nanocrystals exhibit a high level of photocatalytic activity for a plasmonic oxygen evolution reaction at light wavelengths (λ) ≤ 1200 nm.

Optical Hot Spot Generation by the Plasmonic Coupling of Au Nanoparticles in the Nanospaces of Mesoporous Titanium(IV) Oxide.

An reduction technique consisting of chemisorption of 1,3,5,7-tetramethylcyclotetrasiloxane (TMCTS) and subsequent reaction with HAuCl has been developed for depositing Au nanoparticles (NPs) uniformly in the depth direction of a mesoporous TiO nanocrystalline film (Au/TMCTS/mp-TiO). The TMCTS monolayer is further converted into silicon oxide by heating in the air (Au/SiO/mp-TiO). In the absorption spectra of Au/SiO/mp-TiO prepared at varying HAuCl concentrations (), the localized surface plasmon resonance (LSPR) band of Au NPs significantly broadens ≈ 1.

Solar-Driven One-Compartment Hydrogen Peroxide-Photofuel Cell Using Bismuth Vanadate Photoanode.

One-compartment HO-photofuel cells using monoclinic scheelite BiVO film deposited on fluorine-doped tin oxide (ms-BiVO/FTO) as the photoanode, Prussian blue film-coated FTO cathode, and deaerated aqueous electrolyte solution of 0.1 M NaClO and 0.1 M HO were constructed.

In Situ Shape Change of Au Nanoparticles on TiO by CdS Photodeposition: Its Near-Field Enhancement Effect on Photoinduced Electron Injection from CdS to TiO.

Hemisphere-like gold nanoparticles (NPs) were loaded on TiO (Au/TiO) by the deposition-precipitation method. Subsequent photodeposition of CdS on the Au surface of Au/TiO at 50 °C yields Au(core)-CdS(shell) hybrid quantum dots with a heteroepitaxial (HEPI) junction on TiO (Au@#CdS/TiO), whereas nonHEPI Au@CdS/TiO was formed by CdS photodeposition at 25 °C. In the HEPI system, the shape of the Au core changes to an angular shape, whereas it remains in a hemisphere-like shape in the nonHEPI system.

Red-Light-Driven Water Splitting by Au(Core)-CdS(Shell) Half-Cut Nanoegg with Heteroepitaxial Junction.

A key material for artificial photosynthesis including water splitting is heteronanostructured (HNS) photocatalysts. The photocatalytic activity depends on the geometry and dimension, and the quality of junctions between the components. Here we present a half-cut Au(core)-CdS(shell) (HC-Au@CdS) nanoegg as a new HNS plasmonic photocatalyst for water splitting.

Photocatalytic Synthesis of CdS(core)-CdSe(shell) Quantum Dots with a Heteroepitaxial Junction on TiO : Photoelectrochemical Hydrogen Generation from Water.

A major challenge in chemistry for the synthesis of hetero-nanostructures is to build up atomically commensurate interfaces for smooth interfacial charge transfer. Photodeposition of CdSe on a CdS-preloaded mesoporous TiO nanocrystalline film yields CdS(core)-CdSe(shell) quantum dots (CdS@CdSe/mp-TiO ) with a heteroepitaxial nanojunction at 298 K. Two-electrode quantum-dot-sensitized photoelectrochemical (QD-SPEC) cells with the structure photoanode |0.

Coverage control of CdSe quantum dots in the photodeposition on TiO2 for the photoelectrochemical solar hydrogen generation.

CdSe quantum dots (QDs) have successfully been formed on the TiO2 surface by the photodeposition of Se QDs and their subsequent transformation into CdSe QDs (CdSe/TiO2) (Fujishima et al., 2014). The addition of mercaptoacetic acid (MAA) in the second step of the two-step photodeposition process significantly decreases the CdSe particle size and the contact angle against the TiO2 surface to increase the TiO2-surface coverage by CdSe QDs with the particle size distribution sharpened.

Lead selenide-Titanium dioxide heteronanojunction formation by photocatalytic current doubling-induced two-step photodeposition technique.

PbSe quantum dots (QDs) were formed on TiO2 by a two-step photodeposition technique. At the first step, UV-light irradiation of TiO2 in an ethanol solution of H2SeO3 yields Se QDs on the TiO2 surface in a highly dispersed state (Se/TiO2). At the second step, UV-light irradiation of Se/TiO2 in an ethanol solution of Pb(ClO4)2 transforms Se QDs into several tens of nanometer-sized cubic deposits identified as PbSe (PbSe/TiO2) by X-ray diffraction, electronic absorption measurements and X-ray photoelectron spectroscopy.

Simultaneous induction of high level thermal and visible-light catalytic activities to titanium(IV) oxide by surface modification with cobalt(III) oxide clusters.

This study first presents a "TiO2-based eco-catalyst" working in the dark and under visible-light irradiation for the degradation of environmental organic pollutants. Molecular scale cobalt(III) oxide clusters are formed on the surface of highly active anatase TiO2 nanoparticles (Co2O3-TiO2) by the chemisorption-calcination cycle method. Co2O3-TiO2 exhibits very high visible-light activities for the degradation of 2-naphthol and formic acid used as model organic pollutants.

Tin oxide-surface modified anatase titanium(IV) dioxide with enhanced UV-light photocatalytic activity.

[Sn(acac)(2)]Cl(2) is chemisorbed on the surfaces of anatase TiO(2)via ion-exchange between the complex ions and H(+) released from the surface Ti-OH groups without liberation of the acetylacetonate ligand (Sn(acac)(2)/TiO(2)). The post-heating at 873 K in air forms tin oxide species on the TiO(2) surface in a highly dispersed state on a molecular scale ((SnO(2))(m)/TiO(2)). A low level of this p block metal oxide surface modification (~0.

Nickel(II) oxide surface-modified titanium(IV) dioxide as a visible-light-active photocatalyst.

The electronic modification of TiO(2) with highly dispersed NiO particles smaller than ca. 2 nm by the chemisorption-calcination-cycle technique has given rise to a high level of visible-light-activity exceeding that of iron oxide-surface modified TiO(2) simultaneously with the UV-light-activity being significantly increased.

Interfacial chemical bonding effect on the photocatalytic activity of TiO2-SiO2 nanocoupling systems.

TiO(2) nanoparticles (NPs) were deposited on the surfaces of SiO(2) microspheres with a mesoporous structure prepared by a hydrolysis-controlled sol-gel technique. The TiO(2) NPs were firmly combined on the surfaces of SiO(2) microspheres through the interfacial Si-O-Ti bonds. The coupling causes the bandgap widening up to 3.

Photodeposition of metal sulfide quantum dots on titanium(IV) dioxide and the applications to solar energy conversion.

Heteronanojunction systems consisting of narrow gap semiconductors represented by metal sulfides and TiO(2) are highly expected as visible-light-active photocatalysts and the key materials for various photoelectrochemical devices. The common central issue is increasing efficiency of the light-induced interfacial electron transfer from the metal sulfide quantum dots (QDs) to TiO(2). We have newly developed simple and versatile low-temperature photodeposition techniques for directly coupling metal sulfide QDs and TiO(2) by taking advantage of its photocatalysis and the photoinduced surface superhydrophilicity.

Photodeposition of Ag2S quantum dots and application to photoelectrochemical cells for hydrogen production under simulated sunlight.

UV light irradiation of TiO(2) (λ > 320 nm) in a mixed solution of AgNO(3) and S(8) has led to the formation of Ag(2)S quantum dots (QDs) on TiO(2), while Ag nanoparticles (NPs) are photodeposited without S(8). Photoelectrochemical measurements indicated that the Ag(2)S photodeposition proceeds via the preferential reduction of Ag(+) ions to Ag(0), followed by the chemical reaction with S(8). The application of this in situ photodeposition technique to mesoporous (mp) TiO(2) nanocrystalline films coated on fluorine-doped SnO(2) (FTO) electrodes enables formation of Ag(2)S QDs (Ag(2)S/mp-TiO(2)/FTO).

Facile synthesis and catalytic activity of MoS(2)/TiO(2) by a photodeposition-based technique and its oxidized derivative MoO(3)/TiO(2) with a unique photochromism.

UV-light irradiation to TiO(2) in an aqueous ethanol solution of (NH(4))(2)MoS(4) under deaerated conditions has yielded molybdenum(IV) sulfide nanoparticles on a TiO(2) surface (MoS(2)/TiO(2)) to be transformed into molybdenum(VI) oxide species highly dispersed at a molecular level by a subsequent heating at 773K in air (m-MoO(3)/TiO(2)). In HCOOH aqueous solutions, the MoS(2)/TiO(2) system exhibits a high level of photocatalytic activity for H(2) generation, while the m-MoO(3)/TiO(2) system shows unique photochromism.