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Journal of Thermal Analysis and Calorimetry
Authors:
Cornelia Marinescu
,
Ancuta Sofronia
,
Cristina Rusti
,
Roxana Piticescu
,
Viorel Badilita
,
Eugeniu Vasile
,
Radu Baies
, and
Speranta Tanasescu

Introduction TiO 2 is a well-known mineral that occurs in three phases: rutile, anatase, and brookite [ 1 ], each having different structures. All the three phases have been studied for their high photocatalitic activity, high

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Nanocrystalline TiO2/SnO2 composites for gas sensors

An International Forum for Thermal Studies

Journal of Thermal Analysis and Calorimetry
Authors:
M. Radecka
,
A. Kusior
,
A. Lacz
,
A. Trenczek-Zajac
,
B. Lyson-Sypien
, and
K. Zakrzewska

Introduction Metal oxides, such as TiO 2 , SnO 2 , ZnO, WO 3 , and Fe 2 O 3 , are well known for their remarkable ability to change the electrical resistivity in response to oxidizing and reducing gases. Gas sensing properties

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, this method does not require any additional reagent such as ammonia or ozone. Titanium dioxide or titania (TiO 2 ) is usually preferred as an excellent material for photocatalytic applications because of its slower electron–hole recombination

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effect of the oxidants in the UV/TiO 2 system on the degradation rate of 4-chloro-2-methylphenol were found to follow the order IO 4 − > BrO 3 − > H 2 O 2 > O 2 > ClO 3 − [ 6 ]. Syoufian and Nakashima [ 8 ] indicated that the effectiveness of the

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photocatalysts is more and more prevalent [ 1 , 2 ]. This particular field of catalysis initiated intensive scientific interest in the last few decades, particularly for TiO 2 assisted photocatalysis, which has already proved to be a promising tool in water and

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Introduction Titanium dioxide (TiO 2 ) is a well-researched material in the environmental applications of photocatalysis because of its many desirable properties such as being inexpensive, readily available, biologically and

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Introduction The inorganic semiconducting material TiO 2 has attracted great attention because it can photocatalytically split water [ 1 ] and degrade organic pollutants [ 2 – 7 ]. Nevertheless, the wide band gap (3.2 eV) of

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The effect of certain promoters on TiO2 crystal structure transformation was studied by mean thermal and X-ray analyses. It was found that the addition of rutile nuclei and potassium, phosphorus, zinc, magnesium, and aluminium compounds to hydrated titanium dioxide before calcination process influences on the initial temperature and anatase transformation.

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Abstract  

The influence of aliovalent ions such as Mn, Cr, Fe, Mo, and V on the temperature and kinetics of anatase to rutile phase transformation in TiO2 heated in microwave field was studied in this work. The results indicated that heat treatment method and dopants considerably affected the anatase-to-rutile phase transition temperature and kinetics of transformation. The activation energy for anatase to rutile transformation of TiO2 derived from the isothermal data was found to be 328.4 kJ mol-1, which was considerably reduced by the addition of dopants in TiO2 matrix. The activation energy for Mo, Mn and V doped samples was 252.0, 101.3 and 96.4 kJ mol-1, respectively.

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Abstract  

The efficiency of color removal from aqueous Congo Red dye (CR) solution has been investigated in TiO2 suspensions irradiated with artificial UV light. Batch photocatalytic tests were carried out by varying the amount of TiO2 and the irradiation time using the same initial CR concentration. The experimental results indicated that the decolorization rate follows pseudo first-order kinetics with respect to CR concentration. The doses of TiO2 were 0.25, 0.5 and 1.0 g L−1 and the wavelength of incident ultraviolet light was predominantly 254 nm. CR adsorption on the surface of TiO2 is also investigated and described.

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