Blue nano titania made in diffusion flames
2009 (English)In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 11, no 19, 3742-3747 p.Article in journal (Refereed) Published
Blue titanium suboxide nanoparticles (including Magneli phases) were formed directly without any post-processing or addition of dopants by combustion of titanium-tetra-isopropoxide (TTIP) vapor at atmospheric pressure. Particle size, phase composition, rutile and anatase crystal sizes as well as the blue coloration were controlled by rapid quenching of the flame with a critical flow nozzle placed at various heights above the burner. The particles showed a broad absorption in the near-infrared region and retained their blue color upon storage in ambient atmosphere. A high concentration of paramagnetic Ti(3+) centres was found in the substoichiometric particles by electron paramagnetic resonance (EPR) spectroscopy. Furthermore particles with controlled band gap energy from 3.2 to 3.6 eV were made by controlling the burner-nozzle-distance from 10 to 1 cm, respectively. The color robustness and extent of suboxidation could be further enhanced by co-oxidation of TTIP with hexamethyldisiloxane in the flame resulting in SiO(2)-coated titanium suboxide particles. The process is cost-effective and green while the particles produced can replace traditional blue colored, cobalt-containing pigments.
Place, publisher, year, edition, pages
2009. Vol. 11, no 19, 3742-3747 p.
IdentifiersURN: urn:nbn:se:uu:diva-317832DOI: 10.1039/b821590aISI: 000265854000019PubMedID: 19421486OAI: oai:DiVA.org:uu-317832DiVA: diva2:1083102