scholarly journals Mo-modified titanium dioxide as a promising photocatalytically active material

2021 ◽  
Vol 12 (2-2021) ◽  
pp. 131-135
Author(s):  
V. A. Krysanova ◽  
◽  
M. L. Belikov ◽  
S. A. Safaryan ◽  
◽  
...  

The oxide composites based on titanium dioxide modified by molybdenum have been synthesized. The peculiarities of the formation of these composites their physico-chemical and photocatalytic properties have been studied. It is shown that the modification of TiO2 with molybdenum provides obtaining nanodispersed powders (from 8.3 to 12.1 nm) with a free specific surface from 279 to 190 m2/g, respectively. It is shown that the synthesized composites have significantly higher photocatalytic activity (PCA) relative to unmodified TiO2 of similar genesis and industrial titanium dioxide P-25 of Degussa by the example of decomposition of various dyes.

2021 ◽  
Vol 12 (2-2021) ◽  
pp. 214-218
Author(s):  
S. A. Safaryan ◽  
◽  
M. L. Belikov ◽  
V. A. Krysanova ◽  
◽  
...  

The article presents the results of the studies of the physicochemical and photocatalytic properties of titanium dioxide modified with manganese, by the example of decomposition of organic dyes — ferroin and methylene blue. The correlations between the specific surface area and phase composition of the composites with their photocatalytic activity are revealed.


2012 ◽  
Vol 734 ◽  
pp. 364-378 ◽  
Author(s):  
Sajid I. Mogal ◽  
Manish Mishra ◽  
Vimal G. Gandhi ◽  
Rajesh J. Tayade

Titanium dioxide (Titania; TiO2) is one of the most widely used metal oxide semiconductor in the field of photocatalysis for removal of pollutants. It has been noted that titanium dioxide is a research friendly material as its physico-chemical and catalytic properties can be easily altered as per specific application. Since many years, researchers have tried to modify the properties of titanium dioxide by means of doping with metals and non-metals to improve its performance for photocatalytic degradation (PCD) applications. The doping of various metal ions like Ag, Ni, Co, Au, Cu, V, Ru, Fe, La, Pt, Cr, Ce, etc. in titanium dioxide have been found to be influencing the band gap, surface area, particle size, thermal property, etc. and therefore the photocatalytic activity in PCD. Moreover, photocatalytic activity of doped titanium dioxide has been observed in visible light range (i.e., at wavelength >400 nm). In this review, different synthesis route for doping of metal ions in titanium dioxide have been emphasised. The effect of metal dopant on the structural, textural and photocatalytic properties of titanium dioxide has been reviewed.


Author(s):  
Katarzyna A. Michalow ◽  
Andri Vital ◽  
Andre Heel ◽  
Thomas Graule ◽  
Felix A. Reifler ◽  
...  

AbstractPolycrystalline tungsten-doped titanium dioxide nanopowders within a dopant concentration of 0-1 at.% were prepared by a one-step flame spray synthesis (FSS). Mixtures of titanium tetra-isopropoxide dissolved in ethanol and tungsten hexacarbonyl solubilized in tetrahydrofuran were used as precursors. The specific surface area (SSA) of the powders was between 40 and 130 m


2020 ◽  
Vol 64 ◽  
pp. 39-48
Author(s):  
Volodymyr Moklyak ◽  
Volodymyr Chelyadyn ◽  
Andrii Hrubiak ◽  
Bogdan Ostafiychuk ◽  
Volodymyr Kotsyubynsky ◽  
...  

Anatase/brookite nanocomposites were fabricated by the classical method of hydrolysis, additionally using hydrothermal treatment of preformed titanium dioxide sol with tetrabutyl orthotitanate. The influence of hydrothermal processing the buffer solution of TiO2 synthesis on the average particle sizes, specific surface area, pore sizes distributions, optical and photocatalytic properties investigated by X-ray diffraction, low-temperature nitrogen adsorption and UV-Vis spectroscopy. It has been determined that the hydrothermal treatment of pre-prepared titania sol as hydrolysis product leads to rutile formation after annealing at 400°C. Respective model of forming anatase/brookite/rutile nanocomposites was proposed. The changes of bang gap energy of TiO2 were observed and explained by effect of change phase composition and particles size of nanocomposite particles. Methylene blue (MB) photo-oxidation reactions using titanium dioxide nanocomposite were analyzed. Maximal photocatalytic activity of MB oxidation was detected for material with the ratio of the titania phases (anatase : brookite : rutile – 2 : 2 : 1). Synergistic effect between crystallinity, phase ratio, morphology of oxide material, band gap and photocatalytic activity in the anatase/brookite nanocomposites was established.


2011 ◽  
Vol 485 ◽  
pp. 283-286
Author(s):  
Yuji Kondo ◽  
Shinobu Fujihara

Tungsten trioxide (WO3) is known as a visible light responsive photocatalyst, but its photocatalytic activity is relatively low, as compared to that of anatase titanium dioxide (TiO2). To enhance the activity, high specific surface areas are necessary. In this study, WO3particles with a hierarchical architecture, which was assemblies of spherical particles 20 – 30 nm in diameter, were synthesized by the solvothermal method. The hierarchical WO3particles had high specific surface areas and their photocatalytic activity was found to be 2.5 times higher than that of the commercial WO3.


2017 ◽  
Vol 19 (2) ◽  
pp. 56-60 ◽  
Author(s):  
Loghman Karimi

Abstract This study presents a facile approach for the preparation of MoS2 nanosheet decorated by porous titanium dioxide with effective photocatalytic activity. Mesoporous titanium dioxide nanostructures first synthesized by a hydrothermal process using titanium (III) chloride and then the MoS2/TiO2 were prepared through mixing of MoS2 nanosheet with mesoporous titanium dioxide under ultrasonic irradiation. The synthesized nanocomposite was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), and Brunauer-Emmett-Teller (BET) analysis. The results showed that the nanocomposite has mesoporous structure with specific surface area of 176.4 m2/g and pore diameter of 20 nm. The as-prepared MoS2/TiO2 nanocomposites exhibited outstanding photocatalytic activity for dye degradation under sunlight irradiation, which could be attributed to synergistic effect between the molybdenum disulfide nanosheet and mesoporous titanium dioxide. The photocatalytic performance achieved is about 2.2 times higher than that of mesoporous TiO2 alone. It is believed that the extended light absorption ability and the large specific surface area of the 2D MoS2 nanosheets in the nanocomposite, leading to the enhanced photocatalytic degradation activity.


Author(s):  
Dessy Ariyanti ◽  
Junzhe Dong ◽  
Junye Dong ◽  
Wei Gao

<p>Titanium dioxide (TiO2) has gained much attentions for the last few decades due to its remarkable performance in photocatalysis and some other related properties. However, its wide bandgap (~3.2 eV) can only absorb UV energy which is only ~5% of solar light spectrum. The objective of this research was to improve the photocatalytic activity of TiO2 by improving the optical absorption to the visible light range. Here, colored TiO2 nanoparticles range from light to dark grey were prepared via aluminium treatment at the temperatures ranging from 400 to 600 oC. The modified TiO2 is able to absorb up to 50% of visible light (400-700 nm) and shows a relatively good photocatalytic activity in organic dye (Rhodamine B) degradation under visible light irradiation compared with the commercial TiO2. Copyright © 2016 BCREC GROUP. All rights reserved</p><p><em>Received: 10th November 2015; Revised: 7th January 2016; Accepted: 7th January 20 </em></p><p><strong>How to Cite</strong>: Ariyanti, D., Dong, J.Z., Dong, J.Y., Gao, W. (2016). Visible Light Photocatalytic Properties of Modified Titanium Dioxide Nanoparticles via Aluminium Treatment. <em>Bulletin of Chemical Reaction Engineering &amp; Catalysis</em>, 11 (1): 40-47. (doi:10.9767/bcrec.11.1.414.40-47)</p><p><strong>Permalink/DOI</strong>: <a href="http://dx.doi.org/10.9767/bcrec.11.1.414.40-47">http://dx.doi.org/10.9767/bcrec.11.1.414.40-47</a></p>


2006 ◽  
Vol 61 (10) ◽  
pp. 1311-1318 ◽  
Author(s):  
Noureddine Kamil ◽  
Mohamed Khalid El Amrani ◽  
Najiba Benjelloun

Silica gel supported titanium dioxide photocatalysts were prepared by sintering TiO2/SiO2 mixtures under variations of TiO2 content, calcination temperature and calcination time. The method allowed to obtain catalyst samples, which can be used in aqueous suspension and which were found to be easily separated by decantation after the photocatalytic treatment. The photocatalytic efficiency of the catalysts was tested by carrying out the photooxidation of the textile dye Acid Red 88 (AR88) in aqueous solution, used as “model” water pollutant. The obtained photoefficiency results were correlated to catalyst physicochemical characteristics, as determined by Inductively Coupled Plasma (ICP) analysis, X-ray diffraction, specific surface area (BET) and scanning electron microscopy (SEM). No positive correlation has been observed between titanium dioxide content and photocatalytic efficiency. The decrease of photocatalytic activity at high calcination temperature (1000 °C) is attributed to the phase transition anatase/rutile as well as to the decreasing specific surface area. According to SEM analysis, no significant fixation of TiO2 on silica is observed for catalysts prepared at low temperature (400 °C). The observed photocatalytic activity is consequently due to free TiO2 particles. The best efficiency is observed for photocatalyst prepared at 800 °C and containing around fifty percent titanium dioxide.


Author(s):  
E. Krushel'nickaya

Based on the change in the color of an organic dye – rhodamine B, on the surface of concrete under the action of ultraviolet radiation, a theoretical and experimental assessment of the photocatalytic activity of concrete was carried out. Photocatalytic activity was calculated using the obtained coordinates of colorimetry L * a * b *. To assess the performance of the photocatalyst over time, a test was carried out with concrete samples at the age of 7 and 28 days. Titanium dioxide of three types of anatase modification of a foreign manufacturer was used as a photocatalyst in the study. It is shown that the introduction of titanium dioxide into concrete promotes self-cleaning of its surface. The values of discoloration of the dye on the concrete surface were obtained depending on its composition and on the time of exposure to ultraviolet radiation. It was determined that the value of the specific surface area of titanium dioxide affects the photocatalytic activity. It is noted that with the age of concrete samples, there is a noticeable decrease in phototransformation. It was also found that the high specific surface area of titanium dioxide allows it to exhibit its photocatalytic properties over time.


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