TY  - JOUR
AU  - Hou, Tingting
AU  - Luo, Nagchao
AU  - Li, Hongji
AU  - Heggen, Marc
AU  - Lu, Jianmin
AU  - Wang, Yehong
AU  - Wang, Feng
TI  - Yin and Yang Dual Characters of CuOx Clusters for C-C Band Oxidation Driven by Visible Light
JO  - ACS catalysis
VL  - 7
IS  - 6
SN  - 2155-5435
CY  - Washington, DC
PB  - ACS
M1  - FZJ-2017-06686
SP  - 3850 - 3859
PY  - 2017
AB  - Selective cleavage of C–C bonds is pursued as a useful chemical transformation method in biomass utilization. Herein, we report a hybrid CuOx/ceria/anatase nanotube catalyst in the selective oxidation of C–C bonds under visible light irradiation. Using the lignin β-1 model as a substrate offers 96% yields of benzaldehydes. Characterization results by high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and energy-dispersive X-ray spectroscopy element (EDX) mapping reveal that CuOx clusters are highly dispersed on the exposed anatase surface as well as on the nanosized ceria domains. In-depth investigations by Raman and ultraviolet visible diffuse reflectance spectra (UV−vis DRS), together with density functional theory (DFT) calculations, further verify that the CuOx clusters present on the ceria domains increase the concentration of surface defects (Ce3+ ions and oxygen vacancies) and accordingly improve the photocatalytic activity (Yang character); the CuOx clusters decorating on anatase suppress the side reaction (oxy-dehydrogenation without C–C bond cleavage) because of an upward shift in the valence band (VB) edge of anatase (Yin character). Mechanism investigation indicates hydrogen abstraction from β-carbon by photogenerated holes is a vital step in the conversion.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000402851600014
DO  - DOI:10.1021/acscatal.7b00629
UR  - https://juser.fz-juelich.de/record/837916
ER  -