Organized Nanostructured TiO2 Materials: Synthesis, Characterization, Applications
Nanostrukturní oxid titaničitý s řízenou morfologií: Příprava, charakterizace, aplikace
dizertační práce (OBHÁJENO)
Zobrazit/ otevřít
Trvalý odkaz
http://hdl.handle.net/20.500.11956/2575Identifikátory
SIS: 112586
Kolekce
- Kvalifikační práce [19109]
Autor
Vedoucí práce
Oponent práce
Mička, Zdeněk
Šubrt, Jan
Fakulta / součást
Přírodovědecká fakulta
Obor
-
Katedra / ústav / klinika
Katedra anorganické chemie
Datum obhajoby
10. 6. 2008
Nakladatel
Univerzita Karlova, Přírodovědecká fakultaJazyk
Angličtina
Známka
Prospěl/a
CONCLUSIONS It has been known for a long time that material properties change on the nanoscale and are different from those of single crystals or conventional microstructured, monolithic or composite materials32. The presented thesis aimed at demonstration of the diversity in these properties for various morphologies of TiO2. Despite the fact that the chemical composition is identical, the structure of different morphologies matters and it is respon-sible for their specialty. The successfully mastered syntheses of desirable particle size materials open the pathway towards applications taking advantage of size dependent properties. DSC employing 2μm mesoporous TiO2 film as a photoanode exhibited the solar conversion efficiency as high as 4.63% due to the large surface area (roughness fac-tor). Optimized pore size together with the framework consisting of anatase nanocrystals are responsible for the high dye adsorption capacity improving the performance. Incorporating an additional inverse opal layer in DSC represents an example of its further possible upgrade. This optimized set up can increase the short circuit photocurrent effi-ciency of this device of about 26 % (Ref.39). Owing to the diffusion coefficient of an order of 10-13 cm2/s for microcrystalline spinel and even less for nanocrystalline spinel...
CONCLUSIONS It has been known for a long time that material properties change on the nanoscale and are different from those of single crystals or conventional microstructured, monolithic or composite materials32. The presented thesis aimed at demonstration of the diversity in these properties for various morphologies of TiO2. Despite the fact that the chemical composition is identical, the structure of different morphologies matters and it is respon-sible for their specialty. The successfully mastered syntheses of desirable particle size materials open the pathway towards applications taking advantage of size dependent properties. DSC employing 2μm mesoporous TiO2 film as a photoanode exhibited the solar conversion efficiency as high as 4.63% due to the large surface area (roughness fac-tor). Optimized pore size together with the framework consisting of anatase nanocrystals are responsible for the high dye adsorption capacity improving the performance. Incorporating an additional inverse opal layer in DSC represents an example of its further possible upgrade. This optimized set up can increase the short circuit photocurrent effi-ciency of this device of about 26 % (Ref.39). Owing to the diffusion coefficient of an order of 10-13 cm2/s for microcrystalline spinel and even less for nanocrystalline spinel...