scholarly journals Synthesis and Photocatalytic Activity of TiO2 on Phenol Degradation

2021 ◽  
Author(s):  
Muhamad D. Permana ◽  
◽  
Atiek R. Noviyanti ◽  
Putri R. Lestari ◽  
Nobuhiro Kumada ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Photocatalytic Activity ◽  
Band Gap ◽  
Crystallite Size ◽  
Titanium Dioxide Nanoparticles ◽  
Sol Gel ◽  
Phenol Degradation ◽  
High Catalytic Activity ◽  
Titanium Tetraisopropoxide ◽  
Titanium Butoxide

Photocatalysis is a process of accelerating reactions that are assisted by energy from light irradiation. Titanium dioxide (TiO2) is one of the most widely developed photocatalysis materials, and is used because of its high catalytic activity, stability and very affordable. The most commonly used precursors of TiO2 are titanium butoxide (TBOT) and titanium tetraisopropoxide (TTIP). These variations in precursor can lead to phase difference in the formation of TiO2 crystals, which further improves its nature in the activity of photocatalysis. In this study, the sol-gel method was used to synthesize titanium dioxide nanoparticles from variations of TBOT and TTIP. Furthermore, the structure, crystallite size and band gap of TiO2 were determined by X-ray diffraction (XRD) and UV-vis reflectance spectroscopy (DRS). Subsequently, TiO2 photocatalytic activity was evaluated in phenol photodegradation as a contaminant model with UV irradiation. The results showed the structure synthesized from TBOT had a higher amount of anatase, higher crystallinity, smaller crystallite size, larger band gap, and better photocatalytic activity than those from TTIP. Furthermore, it was shown that TiO2 from TBOT had an efficiency of 147% greater than TiO2 P25 Degussa, while TiO2 from TTIP had 66% efficiency compared to TiO2 P25.

scholarly journals Photocatalytic Degradation of Organics by Using Nanocrystalline Titania

2017 ◽  
Vol 2017 ◽  
pp. 1-5 ◽  
Author(s):  
Sana Ahmad ◽  
Anam Nazir ◽  
Tousif Hussain
Keyword(s):  
Titanium Dioxide ◽  
Catalytic Activity ◽  
Titanium Dioxide Nanoparticles ◽  
High Surface ◽  
Sol Gel ◽  
High Surface Area ◽  
Crystalline Form ◽  
Titanium Butoxide ◽  
Fine Spray ◽  
Ft Ir

Titanium dioxide nanoparticles were prepared by a modified sol-gel route. Titanium butoxide was used as precursor and nebulizer was used for a fine spray of particles. The prepared powders were characterized by FT-IR, SEM, XRD, and TGA-DTA methods. The results indicated that nanoparticles with small size and high surface area were synthesized. XRD result indicated that TiO2 nanoparticles were obtained in pure anatase crystalline form with a crystallite size of 40 nm. The catalytic activity of as-synthesized nanoparticles was tested for the degradation of formic acid and toluene.

scholarly journals Synthesis and Characterization of Active Carbon-Titanium Dioxide Composite

2019 ◽  
Vol 31 (5) ◽  
pp. 1176-1180
Author(s):  
Farah S. Daabool ◽  
Falah H. Hussein
Keyword(s):  
Titanium Dioxide ◽  
Photocatalytic Activity ◽  
Activated Carbon ◽  
Uv Light ◽  
Titanium Dioxide Nanoparticles ◽  
Chemical Activation ◽  
Sol Gel ◽  
Chemical Properties ◽  
Growth Conditions ◽  
Activation Technique

Activated carbon was synthesized from Iraqi date palm seeds by physical and chemical activation technique under optimized growth conditions that allow the production of long, well aligned, high-quality activated carbon. Titanium dioxide nanoparticles were prepared using a sol gel method. The activated carbon/TiO2 composites were prepared using simple evaporation and a drying process. The structural, morphological and chemical properties of the prepared activated carbon, TiO2 and activated carbon/TiO2 composite were investigated by X-ray diffraction, Fourier transformed infrared and scanning electron microscope. The photocatalytic activity of activated carbon/TiO2 composite with 10 % of activated carbon was studied and compared with TiO2. The UV light photocatalytic activity was also evaluated by the photocatalytic degradation of phenol in an aqueous solution.

scholarly journals MODIFICATION OF THE NANO TITANIUM BAND GAP REACTIONS OF SOLID DIOXIDE WITH (ANTIMONY) STIBIUM S AND ITS DETERMINATION PHOTOCATALYTIC ACTIVITY

2019 ◽  
Vol 1 (2) ◽  
pp. 161-164
Author(s):  
Moatsasem wdaah Alsalih
Keyword(s):  
Titanium Dioxide ◽  
Photocatalytic Activity ◽  
Band Gap ◽  
Energy Levels ◽  
Sol Gel ◽  
Oh Radicals ◽  
Transferase Activity ◽  
Glutathione S Transferase ◽  
Electron Hole ◽  
Photocatalytic Tio2

This study includes preparation of nanoparticles of titanium dioxide using the sol-gel method and then, the band gap was modified by solid-state reaction with (Antimony) Stibium Sb reductive compounds. Modification reduced the band gap separating energy levels between valance band (VB) and conduction band (CB), therefore; facilitating the transfer of excited electrons from (VB) to (CB). Absorption of the energy from incident photons having the same or larger energy than the energy of the band gap promote the formation of the couple (electron-hole). The resulting (e--h+) couple acts to produce (OH.) radicals. OH. radicals having a high capability to inhibition of glutathione S-transferase activity in Aedes aegypti, mosquitoes that adsorbed on the surface of the photocatalytic TiO2 as a new model of eco-friendly insecticide. 

SYNTHESIS AND CHARACTERIZATION OF TITANIUM DIOXIDE NANOPARTICLES COATED ON FLY ASH

2006 ◽  
Vol 05 (04n05) ◽  
pp. 657-662
Author(s):  
N. WETCHAKUN ◽  
S. PHANICHPHANT
Keyword(s):  
Titanium Dioxide ◽  
Fly Ash ◽  
Titanium Dioxide Nanoparticles ◽  
Phase Particle ◽  
Anatase Phase ◽  
Sol Gel ◽  
Ammonia Solution ◽  
Alcoholic Solution ◽  
Absolute Ethanol ◽  
Titanium Tetraisopropoxide

Titanium dioxide ( TiO 2) nanoparticles in the anatase phase were coated on fly ash by using a sol–gel method. The TiO 2 nanoparticles coated on fly ash were produced from titanium tetraisopropoxide ( Ti ( OPr i )4 3.3 M ) in absolute ethanol, and the fly ash was added into this alcoholic solution. The ratio of TiO 2 nanoparticles to fly ash in the coating process was 1:10 by weight. The ethanolic solution was loaded into a pouch type cellophane membrane and placed for 1 h in a clear solution which containing 1:1 (v/v) ratio of absolute ethanol and distilled water with 0.5–1% concentrated (25%) ammonia solution. After the dialysis process was completed, the mixture was then allowed to dry in an oven at 100–110°C and was calcined in a furnace over the temperatures range of 400–800°C. TiO 2 nanoparticles were then analyzed and characterized by using the techniques of XRD, SEM, EDS, TEM, and BET. The crystalline sizes of anatase form were found to be in the range of 15–20 nm. The characteristics of TiO 2 nanoparticles coated on fly ash were further investigated by utilizing SEM and EDS methodologies. The correlations among crystalline phase, particle size, morphology, and specific surface area were investigated.

Titanium Dioxide Nanoparticles Co-Doped with Fe3+ and Nd3+ Ions for Photocatalysis

2007 ◽  
Vol 121-123 ◽  
pp. 239-242 ◽  
Author(s):  
Yong Luan ◽  
Ping Feng Fu ◽  
Xue Gang Dai
Keyword(s):  
Aqueous Solution ◽  
Titanium Dioxide ◽  
Photocatalytic Activity ◽  
Synergistic Effect ◽  
Titanium Dioxide Nanoparticles ◽  
Sol Gel ◽  
Tio2 Photocatalyst ◽  
Nanocrystalline Tio2 ◽  
Gel Method ◽  
Co Doped

Nanoparticles of titanium dioxide co-doped with Fe3+ and Nd3+ were prepared using the sol-gel method. The prepared TiO2 photocatalyst was characterized with XRD, FTIR and the photocatalytic activity was evaluated by photodegradation of MB aqueous solution. Nanocrystalline TiO2 co-doped with Nd3+ and Fe3+ at optimal concents shows a synergistic effect, which significantly increases the photodegradation activity of TiO2.

scholarly journals Effect of Titanium Dioxide Nanoparticles on the Expression of Efflux Pump and Quorum-Sensing Genes in MDR Pseudomonas aeruginosa Isolates

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 625
Author(s):  
Fatma Y. Ahmed ◽  
Usama Farghaly Aly ◽  
Rehab Mahmoud Abd El-Baky ◽  
Nancy G. F. M. Waly
Keyword(s):  
Titanium Dioxide ◽  
Quorum Sensing ◽  
Biofilm Formation ◽  
Antimicrobial Agents ◽  
Efflux Pump ◽  
Titanium Dioxide Nanoparticles ◽  
Sol Gel ◽  
Efflux Pumps ◽  
Antibiofilm Activity ◽  
The Impact

Most of the infections caused by multi-drug resistant (MDR) P. aeruginosa strains are extremely difficult to be treated with conventional antibiotics. Biofilm formation and efflux pumps are recognized as the major antibiotic resistance mechanisms in MDR P. aeruginosa. Biofilm formation by P. aeruginosa depends mainly on the cell-to-cell communication quorum-sensing (QS) systems. Titanium dioxide nanoparticles (TDN) have been used as antimicrobial agents against several microorganisms but have not been reported as an anti-QS agent. This study aims to evaluate the impact of titanium dioxide nanoparticles (TDN) on QS and efflux pump genes expression in MDR P. aeruginosa isolates. The antimicrobial susceptibility of 25 P. aeruginosa isolates were performed by Kirby–Bauer disc diffusion. Titanium dioxide nanoparticles (TDN) were prepared by the sol gel method and characterized by different techniques (DLS, HR-TEM, XRD, and FTIR). The expression of efflux pumps in the MDR isolates was detected by the determination of MICs of different antibiotics in the presence and absence of carbonyl cyanide m-chlorophenylhydrazone (CCCP). Biofilm formation and the antibiofilm activity of TDN were determined using the tissue culture plate method. The effects of TDN on the expression of QS genes and efflux pump genes were tested using real-time polymerase chain reaction (RT-PCR). The average size of the TDNs was 64.77 nm. It was found that TDN showed a significant reduction in biofilm formation (96%) and represented superior antibacterial activity against P. aeruginosa strains in comparison to titanium dioxide powder. In addition, the use of TDN alone or in combination with antibiotics resulted in significant downregulation of the efflux pump genes (MexY, MexB, MexA) and QS-regulated genes (lasR, lasI, rhll, rhlR, pqsA, pqsR) in comparison to the untreated isolate. TDN can increase the therapeutic efficacy of traditional antibiotics by affecting efflux pump expression and quorum-sensing genes controlling biofilm production.

scholarly journals Photocatalytic Activity Enhancement of Low-pressure Cold-Sprayed TiO2 Coatings Induced by Long-term Water Vapor Exposure

2021 ◽  
Author(s):  
Seremak Wioletta ◽  
Baszczuk Agnieszka ◽  
Jasiorski Marek ◽  
Gibas Anna ◽  
Winnicki Marcin
Keyword(s):  
Titanium Dioxide ◽  
Photocatalytic Activity ◽  
Water Vapor ◽  
Sol Gel ◽  
Low Pressure ◽  
Oxygen Depletion ◽  
Amorphous Structure ◽  
Industrial Applications ◽  
Additional Parameter

AbstractThis work shows that the titanium dioxide coatings obtained by low-pressure cold gas spraying with the use of the sol–gel amorphous TiO2 powder are characterized by photocatalytic activity despite their partial amorphous content. Moreover, the research outcome suggests that the decomposition rate of organic pollutants is enhanced after long-term exposure to moisture. The condensation humidity test is not detrimental to the continuity and integrity of the coating, but the phase composition of coatings changes—with the exposure to water vapor, the portion of the amorphous phase crystallizes into brookite. The mechanism responsible for the conversion of amorphous TiO2 into brookite is attributed to the water-driven dissolution and reprecipitation of TiO6 octahedra. It has been shown that an additional parameter necessary for the stabilization of the brookite is the oxygen depletion of the amorphous structure of titanium dioxide. Considering the results presented in this paper and the advantages of a portable, low-pressure cold spray system for industrial applications, it is expected that TiO2 coatings produced from a sol–gel feedstock powder can be further developed and tested as efficient photocatalysts.

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