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Comparative study of photocatalytic activity of nano-TiO2 & CNT/TiO2 nano-composite in degradation of organoc dyes.

Advance Materials in Industries 02/2012; 1(1):78.

ABSTRACT The photocatalytic activity of nano-TiO2 is well studied. In this work, we enhanced the photocatalytic activity by forming its composite with multi-walled carbon nanotubes (MWCNTs) since CNTs has an excellent conducting property. A nanocomposite of ‘MWCNTs/TiO2’ was prepared by in situ deposition of vapors from carbonaceous source i.e. Toluene over nano-TiO2 coated film as (MWCNTs) in thermal chemical vapor deposition (CVD) furnace. The nano-TiO2 was prepared by reverse miscellization sol-gel method. The characterizations of nano-TiO2 & MWCNTs/TiO2 nanocomposites were done using various sophisticated analytical techniques such as TEM, XRD, UV-Vis spectroscopy etc. Thus produced MWCNTs/TiO2 nanocomposites were used as the catalysts for photo-degradation of acid azo dyes in presence of UV light. Their photocatalytic efficiency was evaluated by measuring comparative rate of photodegradation of these dyes in an aqueous solution. This study shows that MWCNTs/ TiO2 have enhanced photocatalytic activity compared to that of nano-TiO2 under similar conditions. The degradation efficiency obtained by using MWCNTs/TiO2 is about 18 – 20% higher than nano-TiO2 alone under optimized conditions of temperature, catalyst loading, catalyst activation time, flow rate, substrate concentration etc.

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