Intrinsically Activated SrTiO3: Photocatalytic H2 Evolution from Neutral Aqueous Methanol Solution in the Absence of Any Noble-Metal Co-catalyst

Beitrag in einer Fachzeitschrift
(Originalarbeit)


Details zur Publikation

Autor(en): Zhou X, Liu N, Yokosawa T, Osvet A, Miehlich M, Meyer K, Spiecker E, Schmuki P
Zeitschrift: ACS Applied Materials and Interfaces
Jahr der Veröffentlichung: 2018
ISSN: 1944-8244
Sprache: Englisch


Abstract

Noble metal cocatalysts are conventionally a crucial factor in
oxide-semiconductor-based photocatalytic hydrogen generation. In the
present work, we show that optimized high-temperature hydrogenation of
commercially available strontium titanate (SrTiO3) powder can
be used to engineer an intrinsic cocatalytic shell around nanoparticles
that can create a photocatalyst that is highly effective without the
use of any additional cocatalyst for hydrogen generation from neutral
aqueous methanol solutions. This intrinsic activation effect can also be
observed for SrTiO3[100] single crystal as well as Nb-doped SrTiO3[100] single crystal. For all types of SrTiO3
samples (nanopowders and either of the single crystals), hydrogenation
under optimum conditions leads to a surface-hydroxylated layer together
with lattice defects visible by transmission electron microscopy,
electron paramagnetic resonance (EPR), and photoluminescence (PL).
Active samples provide specific defects identified by EPR, PL, and
electron-energy loss spectroscopy as Ti3+ states in a
defective matrix-this is in contrast to the inactive defects formed in
other reductive atmospheres. In aqueous media, active SrTiO3
samples show a significant negative shift of the flatband potential (in
photoelectrochemical as well as in capacitance data) and a lower
charge-transfer resistance for photoexcited electrons. We therefore
ascribe the remarkable cocatalyst-free activation of the material to a
synergy between thermodynamics (altered interface energetics induced by
hydroxylation) and kinetics (charge transfer mediation by suitable Ti3+ states).


FAU-Autoren / FAU-Herausgeber

Liu, Ning Dr.
Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik)
Meyer, Karsten Prof. Dr.
Lehrstuhl für Anorganische und Allgemeine Chemie
Miehlich, Matthias
Zhou, Xuemei
Lehrstuhl für Anorganische und Allgemeine Chemie
Osvet, Andres Dr.
Lehrstuhl für Werkstoffwissenschaften (Materialien der Elektronik und der Energietechnologie)
Schmuki, Patrik Prof. Dr.
Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik)
Spiecker, Erdmann Prof. Dr.
Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)
Yokosawa, Tadahiro Dr.
Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)
Lehrstuhl für Werkstoffwissenschaften (Korrosion und Oberflächentechnik)


Zusätzliche Organisationseinheit(en)
Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)
Interdisziplinäres Zentrum, Center for Nanoanalysis and Electron Microscopy (CENEM)


Zitierweisen

APA:
Zhou, X., Liu, N., Yokosawa, T., Osvet, A., Miehlich, M., Meyer, K.,... Schmuki, P. (2018). Intrinsically Activated SrTiO3: Photocatalytic H2 Evolution from Neutral Aqueous Methanol Solution in the Absence of Any Noble-Metal Co-catalyst. ACS Applied Materials and Interfaces. https://dx.doi.org/10.1021/acsami.8b08564

MLA:
Zhou, Xuemei, et al. "Intrinsically Activated SrTiO3: Photocatalytic H2 Evolution from Neutral Aqueous Methanol Solution in the Absence of Any Noble-Metal Co-catalyst." ACS Applied Materials and Interfaces (2018).

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Zuletzt aktualisiert 2019-27-05 um 16:52