Photocatalytic Decomposition of Acetaldehyde on Different TiO2-Based Materials: A Review

Purification of air from the organic contaminants by the photocatalytic process has been confirmed to be very perspective. Although many various photocatalysts have been prepared and studied so far, TiO2 is still the most commonly used, because of its advantageous properties such as non-toxicity, relatively low cost and high stability. Surface modifications of TiO2 were extensively proceeded in order to increase photocatalytic activity of the photocatalyst under both UV and visible light activations. The intention of this review paper was to summarize the scientific achievements devoted to developing of TiO2-based materials considered as photocatalysts for the photocatalytic degradation of acetaldehyde in air. Influence of the preparation and modification methods on the parameters of the resultant photocatalyst is reviewed and discussed in this work. Affinity of the photocatalyst surfaces towards adsorption of acetaldehyde will be described by taking into account its physicochemical parameters. Impact of the contact time of a pollutant with the photocatalyst surface is analyzed and discussed with respect to both the degradation rate and mineralization degree of the contaminant. Influence of the photocatalyst properties on the mechanism and yield of the photocatalytic reactions is discussed. New data related to the acetaldehyde decomposition on commercial TiO2 were added, which indicated the different mechanisms occurring on the anatase and rutile structures. Finally, possible applications of the materials revealing photocatalytic activity are presented with a special attention paid to the photocatalytic purification of air from Volatile Organic Compounds (VOCs).

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PVA(Polyvincyl Acohol)-assisted Hydrothermal Preparation of Bi25FeO40 and Its Photocatalytic Activity

MRS Proceedings ◽

10.1557/proc-1217-y03-22 ◽

2009 ◽

Vol 1217 ◽

Cited By ~ 2

Author(s):

Li Jianmin ◽

Juyue Song ◽

Jianguo Chen ◽

Shengwen Yu ◽

Dengren Jin ◽

...

Keyword(s):

Photocatalytic Activity ◽

Organic Contaminants ◽

Diffuse Reflectance ◽

Single Phase ◽

Diffuse Reflectance Spectroscopy ◽

Reflectance Spectroscopy ◽

High Photocatalytic Activity ◽

Photocatalytic Decomposition ◽

Hydrothermal Preparation ◽

Degradation Of Methyl Orange

AbstractA PVA-assisted hydrothermal synthesis route was utilized to fabricate single-phase Bi25FeO40 crystallites.X-ray diffraction results indicated that sillenite Bi25FeO40 have been synthesized at the temperature of 200 ℃ using the KOH concentration of 7 M. Scanning electron microscopy showed the morphology of the as-prepared products were cubic shape with side length of 26μm. The band gap of Bi25FeO40 was determined to be 1.8 eV (688 nm) by using UV-vis diffuse reflectance spectroscopy. It was found that Bi25FeO40 exhibited a high photocatalytic activity for the degradation of methyl orange under UV-Vis irradiation, being a potential material for photocatalytic decomposition of organic contaminants.

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Enhanced Removal of Methyl Violet Dye from Aqueous Solution by a Novel Co3O4@SiO2@TiO2-Ag Heterogeneous Semiconductor

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207324666210301090123 ◽

2021 ◽

Vol 24 ◽

Author(s):

Mohammad Ali Ghasemzadeh ◽

Zahar Elyasi ◽

Mohammad Reza Zand Monfared

Keyword(s):

Aqueous Solution ◽

Photocatalytic Activity ◽

Organic Contaminants ◽

Irradiation Time ◽

Low Cost ◽

Sol Gel ◽

Aqueous Media ◽

Methyl Violet ◽

Research Area ◽

Band Gap Energy

Background : This research introduces the application of a novel photocatalyst including Co3O4@SiO2@TiO2-Ag nanocomposite with highly photocatalytic stability and core-shell structure for the removal of toxic methyl violet from aqueous solution. Objective: The removal of toxic dyes and organic contaminants from water is outstanding research area between scientists. Methyl violet as a toxic cationic pollutant has disruptive influence for humans. In this research, with a aim to remove to methyl violet from the wastewater we developed a new photocatalyst including Co3O4@SiO2@TiO2-Ag nanocomposite as a eco-friendly and low-cost nanostructure with high photocatalytic activity in order to reduce the risks of this pollutant from aqueous media. Methods: The Co3O4@SiO2@TiO2-Ag nanostructure was prepared via hydrothermal and sol-gel methods and the structure elucidation of the prepared photocatalyst was analyzed by different spectroscopy techniques including XRD, FT-IR, FE-SEM, TEM, VSM and EDX. Results: Photodegradation of methyl violet in the presence of different structures showed that Co3O4@SiO2@TiO2-Ag is superior photocatalytic activity (about 98% was decomposed after 40 min) compared to the previous shells and pure Co3O4 NPs. Loadings of SiO2@TiO2-Ag nanocomposite over the Co3O4 surface led to the reduction in the band gap energy of visible light and improvement in the photocatalytic activity of Methyl Violet dye for the aqueous phase decomposition. Conclusion: The remarkable benefits of this nanocomposite are highly photocatalytic efficiency in the degradation of methyl violet (almost 100 % within 1 h), easy magnetic separation, low cost, and high chemical stability. The collected results demonstrated the rate of degradation is increased by increasing the irradiation time, while the rate of degradation is decreased by dye concentration.

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The Distribution of Volatile Organics in a Leachate Plume, Gloucester, Ontario

Water Quality Research Journal ◽

10.2166/wqrj.1987.004 ◽

1987 ◽

Vol 22 (1) ◽

pp. 49-64 ◽

Cited By ~ 1

Author(s):

J.F. Devlin ◽

W.A. Gorman

Keyword(s):

Organic Contaminants ◽

Source Area ◽

Unconfined Aquifer ◽

High Concentration ◽

Organic Contamination ◽

Aquifer System ◽

Aquifer Systems ◽

Volatile Organic ◽

Volatile Organic Contaminants ◽

Aquifer Sediments

Abstract The Gloucester Landfill is located near Ottawa, Ontario, on a northeast trending ridge of Quaternary age. The ridge comprises outwash sediments which make up two aquifer systems. A confined system exists next to bedrock, and is overlain by a silty-clayey stratum (the confining layer) which is, in turn, overlain by an unconfined aquifer system. Two independent volatile organic plumes have previously been identified at the landfill: the southeast plume, which has penetrated the confined aquifer system, and the northeast plume which is migrating in the unconfined aquifer. The distribution of volatile organic contaminants at the northeast plume site appears to be a function of two factors: (1) heterogeneities in the aquifer sediments are causing the channeling of contaminants through a narrow path; (2) the low fraction of organic carbon in the unconfined aquifer sediments at the northeast site is resulting in little retardation of the contaminants there, relative to those at the southeast site. Acetate was the only volatile fatty acid detected in the leachate. It was measurable only in areas where the volatile organic contamination was significant. Although methane was detected in the contaminated sediments, suggesting that microbial activity was present, the high concentration of acetate (>1000 ppm) which was detected down-gradient from the source area indicates that any biodegradation which is occurring is proceeding at a very slow rate.

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Impact of Al doping on a hydrothermally synthesized β-Ga2O3 nanostructure for photocatalysis applications

RSC Advances ◽

10.1039/d1ra00021g ◽

2021 ◽

Vol 11 (13) ◽

pp. 7338-7346

Author(s):

Sunjae Kim ◽

Heejoong Ryou ◽

In Gyu Lee ◽

Myunghun Shin ◽

Byung Jin Cho ◽

...

Keyword(s):

Photocatalytic Activity ◽

Grain Boundary ◽

Redox Potential ◽

Surface Area ◽

Crystal Defect ◽

Oxygen Defect ◽

Al Doping ◽

Photocatalytic Reactions

The photocatalytic activity is correlated with different parameters affecting the photocatalytic reactions; redox potential (RP), surface area (SA), crystal defect (CD), oxygen defect (OD), and grain-boundary induced defect (GD).

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Vanadium doped CaTiO3 cuboids: Role of vanadium in improving the photocatalytic activity

Nanoscale Advances ◽

10.1039/d1na00468a ◽

2021 ◽

Author(s):

Harsha Bantawal ◽

Sandhya U. Shenoy ◽

Denthaje Krishna Bhat

Keyword(s):

Photocatalytic Activity ◽

Water Splitting ◽

Dye Degradation ◽

Low Cost ◽

Physicochemical Stability ◽

Photocatalytic Dye Degradation

CaTiO3 has attracted enormous interest in the field of photocatalytic dye degradation and water splitting owing to its low cost, excellent physicochemical stability and structural tunability. Herein, we have developed...

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P-doped CdS integrated with multiphasic MoSe2 nanosheets accomplishing prominent photocatalytic activity for hydrogen evolution

Catalysis Science & Technology ◽

10.1039/d1cy00951f ◽

2021 ◽

Author(s):

Xuanxuan Yang ◽

Hong Yang ◽

Tiantian Zhang ◽

Yongbing Lou ◽

Jinxi Chen

Keyword(s):

Photocatalytic Activity ◽

Transition Metal ◽

Hydrogen Evolution ◽

Low Cost ◽

Cds Nanorods

Rational modulation of low-cost and versatile Cd-based photocatalysts coupled with transition metal diselenides is favorable to reinforcing the performance of hydrogen evolution. Herein, the P-doped CdS nanorods (denoted as PCS)...

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Mechanisms and adsorption capacities of biochar for the removal of organic and inorganic pollutants from industrial wastewater

International Journal of Environmental Science and Technology ◽

10.1007/s13762-020-03060-w ◽

2020 ◽

Author(s):

T. G. Ambaye ◽

M. Vaccari ◽

E. D. van Hullebusch ◽

A. Amrane ◽

S. Rtimi

Keyword(s):

Organic Contaminants ◽

Pyrolysis Temperature ◽

Low Cost ◽

Industrial Effluents ◽

Economic Benefits ◽

Inorganic Pollutants ◽

Solution Ph ◽

Adsorption Mechanisms ◽

Adsorption Capacities ◽

Temperature Solution

AbstractCurrently, due to the rapid growth of urbanization and industrialization in developing countries, a large volume of wastewater is produced from industries that contain chemicals generating high environmental risks affecting human health and the economy if not treated properly. Consequently, the development of a sustainable low-cost wastewater treatment approach has attracted more attention of policymakers and scientists. The present review highlights the recent applications of biochar in removing organic and inorganic pollutants present in industrial effluents. The recent modes of preparation, physicochemical properties and adsorption mechanisms of biochar in removing organic and inorganic industrial pollutants are also reviewed comprehensively. Biochar showed high adsorption of industrial dyes up to 80%. It also discusses the recent application and mechanism of biochar-supported photocatalytic materials for the degradation of organic contaminants in wastewater. We reviewed also the possible optimizations (such as the pyrolysis temperature, solution pH) allowing the increase of the adsorption capabilities of biochar leading to organic contaminants removal. Besides, increasing the pyrolysis temperature of the biochar was seen to lead to an increase in its surface area, while it decreases their amount of oxygen-containing functional groups, consequently leading to a decrease in the adsorption of metal (loid) ions present in the medium. Finally, the review suggests that more research should be carried out to optimize the main parameters involved in biochar production and its regeneration methods. Future efforts should be also carried out towards process engineering to improve its adsorption capacity to increase the economic benefits of its implementation.

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