Naslov
Transmission electron microscopy of annealed titanate nanotubes for catalytic applications

Autori
Plodinec, Milivoj ; Gajović, Andreja ; Čeh, Miran

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, neobjavljeni rad, znanstveni

Izvornik
2nd Adriatic School of Nanoscience / - , 2012

Skup
2nd Adriatic School of Nanoscience - ASON

Mjesto i datum
Dubrovnik, Hrvatska, 02.09.2012. - 07.09.2012

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Titania nanotubes ; Functionalization ; Photocatalysis

Sažetak
Titanate (TiNT) and TiO2 nanotubes are a new mesoporous nanostructured materials based on titanium dioxide, attract huge interest in the last few years due to their attractive properties [1]. The properties include: the ease of synthesis with a relatively low cost (especially in comparison to the carbon nanotubes), a high specific surface area, ability to functionalize the surface via chemisorptions or the ion-exchange of species, and the possibility of reversible gas adsorption. Current application areas of titanium oxide nanostructures include: dye-sensitized solar cells ; the photo-catalytic degradation of environmental contaminants ; gas- and liquid-phase catalysis, function in solid-state lithium batteries, and biosensors [1]. With the aim to increase photo-catalytic properties of titanate base nanotubes, we studied the influence of the temperature treatment of H2Ti3O7 in various atmospheres to morphology, phase transition and light absorption. Titanate nanotubes (TiNT-H) were prepared by hydrothermal treatment of TiO2 powder with NaOH and subsequent ion exchange by HCl, and then calcined on several temperatures. Temperature treatments were performed in high temperature Astro furnace. Changes in morphology and catalytic properties were studied by TEM, HRTEM, Raman spectroscopy, XRD, BET srfaces analysis, and UV/Vis/NIR spectroscopy. Before thermal treatment TiNT – H show tubular morphology with high specific surface area of about 400 m2/g, inner diameter of 7-9 nm and outer diameter 9 – 12 nm, and average length from 300 nm up to 1 μm (Fig. 1a and 1b). After thermal treatment a complete degradation of tubular structure and the formation of elongated nanocrystals, nanorods or nanowires depending of the annealing atmosphere were observed. The typical morphology of elongated nanocrystals with well-defined crystal lattice and average size 10 – 20 nm is shown in Figures 1c and 1d. This study demonstrates that thermal treatment of TiNT–H nanotubes in selected atmospheres significantly influenced on crystal structure and light absorption of TiO2 nanostructures in visible and IR region (Fig 2). High activity in visible and IR region obtained powder could increase photocatalytic properties of titania nanotubes.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija

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