Visible Light Photo-oxidation in Au Nanoparticle Sensitized SrTiO₃:Nb Photoanode

Abstract

Au nanoparticle decorated SrTiO 3 :Nb (Au/SrTiO 3 :Nb) has been demonstrated as a photoanode for photo-oxidation under visible light. The visible light photo-oxidation is a result of the generation of the hot electrons in the Au nanoparticles, which are subsequently injected into the SrTiO 3 :Nb conduction band. This leaves behind holes for electrochemical oxidation, which can oxidize a variety of chemical species with redox potentials ranging from 0 to 1.23 V vs RHE. The visible light response is most enhanced at the surface plasmon resonance energy of the Au nanoparticles, which we believe reflect the high optical density near the plasmon resonance for the sensitization. This work demonstrates a general route to impart visible light utilization to a wide band gap semiconductor for various energy conversion and environmental applications, including solar fuel generation and organic pollutant decomposition.

Enhanced Stability and Thickness‐Independent Oxygen Evolution Electrocatalysis of Heterostructured Anodes with Buried Epitaxial Bilayers

“…In an effort to reduce the depletion layer width x d (in Mott–Schottky theory where q is the magnitude of the electronic charge, V bi the built‐in potential, and N D the ionized donor atom density) of the 2 at% Nb doped SrTiO 3 (denoted as NSTO) support structure, we have used epitaxial bilayers comprised of La doped SrTiO 3 (denoted as LSTO), an oxide stable in alkaline conditions but exhibiting high permittivity in bulk (ε STO = 300ε o ) and low electronic mobility (measured LSTO film Hall mobility μ H = 5 cm 2 V −1 s −1 ), and La doped BaSnO 3 (denoted as BLSO), unstable in alkaline conditions, but exhibiting lower permittivity in bulk (ε BSO = 25ε o ) and higher electronic mobility (measured BLSO film Hall mobility μ H = 75 cm 2 V −1 s −1 ).…”

Promoting Photocatalytic Overall Water Splitting by Controlled Magnesium Incorporation in SrTiO3 Photocatalysts

“…where C sc is the capacitance of the space‐charge layer, e is the charge of the electron, ϵ is the dielectric constant of the semiconductor (300 for SrTiO 3 ), ϵ 0 is the vacuum permittivity of free space, N is the donor density (electron donor concentration for an n‐type semiconductor or hole acceptor concentration for a p‐type semiconductor), E appl is the applied potential, E fb is the flat‐band potential, k is the Boltzmann constant, and T is the absolute temperature. The flat‐band potential ( E fb ) and donor intensity ( N ) were calculated and are summarized in Table .…”

Nitrogen and sulfur co-doped fluorescent carbon dots for the trapping of Hg(ii) ions from water

“…The photostability of the CDs is another significant property, especially in fluorescence detection methods. 41 Therefore, the emission profile of the CDs was scrutinized under UV irradiation (365 nm) for 180 minutes (Fig. 1F) and no change in the fluorescence intensity was observed, thus substantiating the photo-stability of the CDs.…”