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

Journal Article · Tue Aug 01 00:00:00 EDT 2006 · Journal of Physical Chemistry. B, Condensed Matter, Materials, Surfaces, Interfaces and Biophysical Chemistry

DOI:https://doi.org/10.1021/jp062507n· OSTI ID:1152421

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

In this work α-Cr₂O₃/α-Fe₂O₃ core-shell polycrystalline nanostructures were synthesized by using α-Cr₂O₃ nanoparticles as seed crystals during aqueous nucleation. The formation of α-Fe₂O₃ polycrystallites on α-Cr₂O₃ surfaces was 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” α-Fe₂O₃ particles of the same size were measured with femtosecond transient absorption spectroscopy. The results show the carrier lifetimes decay within a few picoseconds regardless of sample. Finally, 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 Office of Science (SC), Biological and Environmental Research (BER)
• OSTI ID: 1152421
• Journal Information: Journal of Physical Chemistry. B, Condensed Matter, Materials, Surfaces, Interfaces and Biophysical Chemistry, Vol. 110, Issue 34; ISSN 1520-6106
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English