Abstract
Mesoporous TiO2 is prepared by sol–gel process with a triblock copolymer as an organic template and aqueous TiOCl2 solution as inorganic precursor. The XRD patterns reveal that only the anatase phase can be observed in mesoporous TiO2, regardless of the different calcining temperatures, and with increasing calcining temperature the grain size gradually increases. The grain sizes of TiO2 increased from 4.7 to 11.9 nm with calcining temperature increasing from 300 to 400 °C. The pore size and the surface area evaluated from the Barrett–Joyner–Halenda model and Brunauer–Emmett–Teller method indicated that the average pore sizes increased from 87 to 153 Å and specific surface areas decreased from 179.71 to 74.31 m2/g for 300–400 °C calcination. The relationship between the optical band gap (E g) and microstructure of anatase has been determined and discussed. The quantum confinement effect is observed at grain sizes lower than 10 nm, and the estimated E g shifts from 3.32 to 3.46 eV. These results suggest that there are potential applications of mesostructured TiO2 with nanocrystals in the design of optical devices and photocatalysts.
Similar content being viewed by others
References
Gratzel M (2001) J Sol-Gel Sci Technol 22:7
Tanaka Y, Suganuma M (2001) J Sol-Gel Sci Technol 22:83
Traversa E, Di Vona ML, Licoccia S, Sacerdoti M, Carotta MC, Crema L, Martinelli G (2001) J Sol-Gel Sci Technol 22:167
Di Claudio D, Phani AR, Santucci S (2007) Opt Mater 30:279
Li YZ, Lee N-H, Song JS, Lee EG, Kim S-J (2005) Res Chem Intermed 31:309
Kosacki I, Anderson HU (2000) Ionics 6:294
Zhang WF, Zhang MS, Yin Z (2000) Physica Status Solidi (a) 179:319
Peng HW, Li JB (2008) J Phys Chem C 112:20241
Brus LE (1984) J Chem Phys 80:4403
Brus LE (1986) J Phys Chem 90:2555
Wang Y, Suna A, Mahler W, Kasowski R (1987) J Chem Phys 87:7315
Stone VF, Davis RJ (1998) Chem Mater 10:1468
Bosc F, Ayral A, Albouy P, Guizard C (2003) Chem Mater 15:2463
Zhao LL, Yu Y, Song LX, Hu XF, Larbot A (2005) Appl Surf Sci 239:285
Shioy Y, Ikeue K, Ogawa M, Anpo M (2003) Appl Catal A Gen 254:251
Qi ZM, Honma I, Zhou H (2006) Appl Phys Lett 88:053503
Vogel R, Meredith P, Kartini I, Harvey M, Riches JD, Bishop A, Heckenberg N, Trau M, Rubinsztein-Dunlop H (2003) Chem Phys Chem 4:595
Barrett EP, Joyner LG, Halenda PP (1951) J Am Chem Soc 73:373
Brunauer S, Emmett PH, Teller E (1938) J Am Chem Soc 60:309
Cullity BD (1978) Elements of X-ray diffraction. Addison-Wesley, Reading
Wang K, Morris MA, Holmes JD (2005) Chem Mater 17:1269
Sinha AK, Suzuki K (2005) J Phys Chem B 109:1708
Gregg SJ, Sing KSW (1982) Adsorption, surface area and porosity. Academic Press, London
Reddy KM, Manorama SV, Reddy AR (2002) Mater Chem Phys 78:239
Tian GL, He HB, Shao JD (2005) Chin Phy Lett 22:1787
Acknowledgments
This work was financially supported by the National Science Council of Taiwan, the Republic of China, grant No. NSC 97-2221-E-020-024 and NSC 98-2221-E-020-020, which are gratefully acknowledged.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Lee, YC., Chang, Y.S., Teoh, L.G. et al. The effects of the nanostructure of mesoporous TiO2 on optical band gap energy. J Sol-Gel Sci Technol 56, 33–38 (2010). https://doi.org/10.1007/s10971-010-2269-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10971-010-2269-7