Excited Carrier Dynamics of α-Cr2O3/α-Fe2O3 Core-Shell Nanostructures

Journal Article · Sat Aug 05 00:00:00 EDT 2006 · Journal of Physical Chemistry B, 110(34):16937-16940

DOI:https://doi.org/10.1021/jp062507n· OSTI ID:891140

Xiong, Gang; Joly, Alan G; Holtom, Gary R; Wang, Chong M; McCready, David E; Beck, Kenneth M; Hess, Wayne P

In this work ?-Cr2O3/?-Fe2O3 core-shell polycrystalline nanostructures were synthesized using ?-Cr2O3 nanoparticles as seed crystals during aqueous nucleation. The formation of ?-Fe2O3 polycrystallites on ?-Cr2O3 surfaces were confirmed by x-ray diffraction, transmission electron microscopy, and energy dispersive x-ray analysis. The excited state relaxation dynamics of as-grown core-shell structures and ''pure'' ?-Fe2O3 particles of the same size were measured using femtosecond transient absorption spectroscopy. The results show the carrier lifetimes decay within a few picoseconds regardless of sample. This is likely due to fast recombination/trapping of carriers to defects and iron d-states.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 891140
• Report Number(s): PNNL-SA-50398; 11102; TRN: US200621%%43
• Journal Information: Journal of Physical Chemistry B, 110(34):16937-16940, Journal Name: Journal of Physical Chemistry B, 110(34):16937-16940
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION SPECTROSCOPY
CARRIER LIFETIME
D STATES
DEFECTS
EXCITED STATES
IRON OXIDES
NANOSTRUCTURES
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
CHROMIUM OXIDES
Environmental Molecular Sciences Laboratory