Volume 3, Issue 10, October 2015
- SPECIAL TOPIC: PHOTOCATALYSIS
- Invited Articles
Exceptional enhancement of H2 production in alkaline environment over plasmonic Au/TiO2 photocatalyst under visible light3(2015); http://dx.doi.org/10.1063/1.4921783View Description Hide Description
A reaction environment modulation strategy was employed to promote the H2 production over plasmonic Au/semiconductor composites. It is shown that the fast consumption of the holes in plasmonic Au nanoparticles by methanol in alkaline reaction environment remarkably increases H2 generation rate under visible light. The photocatalytic reaction is mainly driven by the interband transition of plasmonic Au nanoparticles, and the apparent quantum efficiency of plasmon-assisted H2 production at pH 14 reaches 6% at 420 nm. The reaction environment control provides a simple and effective way for the highly efficient solar fuel production from biomass reforming through plasmonic photocatalysis in future.
Photocatalytic oxidation of the organic monolayers on TiO2 surface investigated by in-situ sum frequency generation spectroscopy3(2015); http://dx.doi.org/10.1063/1.4921954View Description Hide Description
In-situ vibrational sum frequency generation (SFG) spectroscopy has been employed to investigate the photocatalytic oxidation of two types of well-ordered organic monolayers, namely, an arachidic acid (AA) monolayer prepared by the Langmuir-Blodgett method and an octadecyltrichlorosilane (OTS) monolayer prepared by the self-assembling method, on a TiO2 surface under ultraviolet (UV) irradiation. The extremely high sensitivity and unique selectivity of the SFG spectroscopy enabled us to directly probe the structural changes in these monolayers during the surface photocatalytic oxidation and further elucidate their reaction mechanisms at a molecular level. It was revealed that the ordering of the monolayers during the photocatalytic reaction is strongly dependent on their interaction with the substrate; the AA monolayer maintains its ordered conformation until the final oxidation stage, while the OTS monolayer shows a large increase in disordering during the initial oxidation stage, indicating a different photocatalytic reaction mechanism of the two monolayers on the TiO2 surface.
- Contributed articles
3(2015); http://dx.doi.org/10.1063/1.4919700View Description Hide Description
We investigate the impact of post-treatment on photocatalytic oxidation activity of (111) oriented NaNbO3 film prepared by pulse laser deposition. Some impurities such as Na 2 Nb 4O11 and bigger particles appear in the treated samples. The activity of rhodamine B degradation with N2 purge increases with the amount of ⋅OH, the sample treated under H2/Ar(7%) being the highest activity, followed by under air and untreated one; the opposite trend is observed when the system was without N2 purge.