TY - JOUR
T1 - H2 Generation with (Mixed) Plasmonic Cu/Au-TiO2 Photocatalysts
T2 - Structure–Reactivity Relationships Assessed by in situ Spectroscopy
AU - Priebe, Jacqueline B.
AU - Radnik, Jörg
AU - Kreyenschulte, Carsten
AU - Lennox, Alastair J J
AU - Junge, Henrik
AU - Beller, Matthias
AU - Brückner, Angelika
PY - 2017/3/20
Y1 - 2017/3/20
N2 - Monometallic Cu and bimetallic Cu/Au-TiO2 catalysts were prepared by impregnation (IM) and reductive precipitation (RP) methods in sequential (SP) and simultaneous mode (CP) and tested for photocatalytic H2 generation from H2O/methanol mixtures with visible (400–700 nm) and UV/Vis light (320–500 nm). Comprehensive studies by high-resolution (HR)-STEM, X-ray photoelectron spectroscopy (XPS), and different in situ methods (X-ray absorption near-edge structure (XANES), UV/Vis, and EPR spectroscopy) revealed that IM leads to dispersed surface Cu species with no clear particle formation, which is poorly active under visible light, whereas plasmonic Cu0 nanoparticles formed by RP are about three times more active under the same conditions. In Cu/Au-TiO2 catalysts prepared by RP-SP, highly dispersed Cu surface species boost H2 production under UV/Vis light, owing to the effective separation within TiO2 and electron trapping by Cu, whereas small Cu0 and Au0 particles remain widely separated. When Cu/Au-TiO2 catalysts are prepared by RP-CP, mixed Cu/Au particles of uniform size (4–8 nm) provide the highest H2 evolution rates under visible light, owing to effective surface plasmon resonance absorption.
AB - Monometallic Cu and bimetallic Cu/Au-TiO2 catalysts were prepared by impregnation (IM) and reductive precipitation (RP) methods in sequential (SP) and simultaneous mode (CP) and tested for photocatalytic H2 generation from H2O/methanol mixtures with visible (400–700 nm) and UV/Vis light (320–500 nm). Comprehensive studies by high-resolution (HR)-STEM, X-ray photoelectron spectroscopy (XPS), and different in situ methods (X-ray absorption near-edge structure (XANES), UV/Vis, and EPR spectroscopy) revealed that IM leads to dispersed surface Cu species with no clear particle formation, which is poorly active under visible light, whereas plasmonic Cu0 nanoparticles formed by RP are about three times more active under the same conditions. In Cu/Au-TiO2 catalysts prepared by RP-SP, highly dispersed Cu surface species boost H2 production under UV/Vis light, owing to the effective separation within TiO2 and electron trapping by Cu, whereas small Cu0 and Au0 particles remain widely separated. When Cu/Au-TiO2 catalysts are prepared by RP-CP, mixed Cu/Au particles of uniform size (4–8 nm) provide the highest H2 evolution rates under visible light, owing to effective surface plasmon resonance absorption.
KW - bimetallic catalysts
KW - hydrogen generation
KW - in situ spectroscopy
KW - photocatalysis
KW - surface plasmon resonance
UR - http://www.scopus.com/inward/record.url?scp=85013115178&partnerID=8YFLogxK
U2 - 10.1002/cctc.201601361
DO - 10.1002/cctc.201601361
M3 - Article (Academic Journal)
AN - SCOPUS:85013115178
SN - 1867-3880
VL - 9
SP - 1025
EP - 1031
JO - ChemCatChem
JF - ChemCatChem
IS - 6
ER -