TY - JOUR
T1 - Photomodification of heteroleptic titanium-based, complex metal alkoxides
AU - Schneider, Z. V.
AU - Simmons-Potter, K.
AU - Boyle, T. J.
N1 - Funding Information:
The authors would like to acknowledge B.G. Potter Jr., J.D. Musgraves, and N. Jacobsen for their contributions to this work. This research was supported by the United States Department of Energy, Office of Basic Energy Sciences. Partial support was also provided by the University of Arizona, State of Arizona, TRIF Optics Initiative Program and by Sandia National Laboratories. Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company for the United States Department of Energy’s National Nuclear Security Administration under Contract DE-AC04-94AL85000.
PY - 2009/4/15
Y1 - 2009/4/15
N2 - A heteroleptic titanium metal alkoxide (OPy)2Ti(4MP)2, where OPy = NC5H4(CH2O)-2 and 4MP = OC6H4(SH)-4, was investigated as a candidate precursor for the solution-based (sol-gel) synthesis of titanium oxide via the photoactivation of intermolecular linking reactions (e.g., hydrolysis/condensation). The evolution of the electronic structure of the solution-based molecule arising from conventional (dark) chemical reaction kinetics was compared with that of samples exposed to ultraviolet (UV) radiation at wavelengths of λ = 337.1 nm and 405 nm using UV-visible absorption spectroscopy. Photoinduced changes in the spectra were examined as a function of both the incident wavelength of exposure and the total fluence. Experimental results confirm the UV-induced modification of spectral absorption features, attributed to ligand-localized and charge transfer transitions accompanied by structural changes associated with hydrolysis and condensation. The photoenhancement of reaction kinetics in these processes was confirmed by the increased modification of the absorption features in the solution spectra, which saturated more rapidly under UV-illumination than under dark conditions. Similar saturation behaviors were observed for both the 337.1 nm and the 405 nm incident wavelengths with the same total deposited energy density indicating a relative insensitivity of the photoinduced response to excitation energy for the wavelengths and fluences studied.
AB - A heteroleptic titanium metal alkoxide (OPy)2Ti(4MP)2, where OPy = NC5H4(CH2O)-2 and 4MP = OC6H4(SH)-4, was investigated as a candidate precursor for the solution-based (sol-gel) synthesis of titanium oxide via the photoactivation of intermolecular linking reactions (e.g., hydrolysis/condensation). The evolution of the electronic structure of the solution-based molecule arising from conventional (dark) chemical reaction kinetics was compared with that of samples exposed to ultraviolet (UV) radiation at wavelengths of λ = 337.1 nm and 405 nm using UV-visible absorption spectroscopy. Photoinduced changes in the spectra were examined as a function of both the incident wavelength of exposure and the total fluence. Experimental results confirm the UV-induced modification of spectral absorption features, attributed to ligand-localized and charge transfer transitions accompanied by structural changes associated with hydrolysis and condensation. The photoenhancement of reaction kinetics in these processes was confirmed by the increased modification of the absorption features in the solution spectra, which saturated more rapidly under UV-illumination than under dark conditions. Similar saturation behaviors were observed for both the 337.1 nm and the 405 nm incident wavelengths with the same total deposited energy density indicating a relative insensitivity of the photoinduced response to excitation energy for the wavelengths and fluences studied.
KW - Optical spectroscopy
KW - Photocatalysis
KW - Photoinduced effects
KW - Solution chemistry
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U2 - 10.1016/j.jnoncrysol.2009.02.002
DO - 10.1016/j.jnoncrysol.2009.02.002
M3 - Article
AN - SCOPUS:63149150732
VL - 355
SP - 536
EP - 540
JO - Journal of Non-Crystalline Solids
JF - Journal of Non-Crystalline Solids
SN - 0022-3093
IS - 9
ER -