Please use this identifier to cite or link to this item:
|Title:||Tunable hierarchical TiO2 nanostructures by controlled annealing of electrospun fibers: Formation mechanism, morphology, crystallographic phase and photoelectrochemical performance analysis|
|Source:||Kumar, P.S., Nizar, S.A.S., Sundaramurthy, J., Ragupathy, P., Thavasi, V., Mhaisalkar, S.G., Ramakrishna, S. (2011-07-14). Tunable hierarchical TiO2 nanostructures by controlled annealing of electrospun fibers: Formation mechanism, morphology, crystallographic phase and photoelectrochemical performance analysis. Journal of Materials Chemistry 21 (26) : 9784-9790. ScholarBank@NUS Repository. https://doi.org/10.1039/c1jm10859j|
|Abstract:||Highly crystalline hierarchical TiO2 nanostructures of morphology ranging from one-dimensional regular fibers, hollow tubes, porous rods and spindles were achieved from electrospun TiO2/composite fibers by annealing at temperatures ranging from 400°C, 500°C, 600°C, 700°C, and 800°C, with a ramp rate of 5°C min -1, and at a pressure of 1 mbar. Crystallographic structure, crystallite size, surface morphology and surface area of annealed TiO 2 nanostructures were analysed by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM) and Brunauer-Emmett-Teller (BET) method. The analysis of post-annealing process on electrospun TiO2 nanofibers showed an orderly change in the crystallographic phase transformation with corresponding change in their surface morphologies. XRD and HRTEM analysis confirmed the phase transformation of highly crystalline anatase phase to rutile with crystallite size varied from 11 nm to 36 nm upon tuning the annealing temperature. Interestingly, TiO2 nanostructures annealed at 700°C showed the formation of biphasic TiO2 hollow tubes with stoichiometry phase compositions of 45.74% anatase and 54.25% rutile. A possible formation mechanism was proposed based on series of temperature-dependent experiments. To evaluate the potential use of these TiO2 nanostructures, dye sensitized solar cell (DSSC) was fabricated using the post-annealed TiO2 nanostructures as photoanode. A higher conversion efficiency (η) of 4.56% with a short circuit current (Jsc) of 8.61 mA cm-2 was observed for highly ordered porous anatase TiO 2 nanorods obtained upon annealing at 500°C under simulated AM1.5 G (100 mW cm-2), confirming that surface area of TiO2 resulted out of porous structure played dominant role. © 2011 The Royal Society of Chemistry.|
|Source Title:||Journal of Materials Chemistry|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Apr 3, 2018
WEB OF SCIENCETM
checked on Apr 3, 2018
checked on Mar 12, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.