Photoluminescence of anatase and rutile TiO2 particles.
Nonaqueous reactions between titanium(IV) chloride and alcohols (benzyl alcohol or n-butanol) were used for the synthesis of anatase TiO2 particles, while rutile TiO2 particles were synthesized in aqueous media by acidic hydrolysis of titanium(IV) chloride. The X-ray diffraction measurements proved the exclusive presence of either the anatase or the rutile phase in prepared samples. The photoluminescence of both kinds of particles (anatase and rutile) with several well-resolved peaks extending in the visible spectral region was observed, and the quantum yield at room temperature was found to be 0.25%. Photon energy up-conversion from colloidal anatase and rutile TiO2 particles was observed at low excitation intensities. The energy of up-converted photoluminescence spans the range of emission of normal photoluminescence. The explanation of photon energy up-conversion involves mid-gap energy levels originating from oxygen vacancies.
Abazović
Nadica D
ND
Vincca Institute of Nuclear Sciences, P.O. Box 522, 11001 Belgrade, Serbia.
Comor
Mirjana I
MI
Dramićanin
Miroslav D
MD
Jovanović
Dragana J
DJ
Ahrenkiel
S Phillip
SP
Nedeljković
Jovan M
JM
D020001:1-Butanol / Q000737:chemistry; D019905:Benzyl Alcohol / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry; D006868:Hydrolysis; D008163:Luminescent Measurements / Q000379:methods*; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D012680:Sensitivity and Specificity; D014025:Titanium / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
D002712:Chlorides; D014867:Water; C009495:titanium dioxide; D020001:1-Butanol; D014025:Titanium; D019905:Benzyl Alcohol