scholarly journals Au/ZnO Hybrid Nanostructures on Electrospun Polymeric Mats for Improved Photocatalytic Degradation of Organic Pollutants

Water ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1787 ◽  
Author(s):  
Laura Campagnolo ◽  
Simone Lauciello ◽  
Athanassia Athanassiou ◽  
Despina Fragouli
Keyword(s):  
Photocatalytic Degradation ◽  
Organic Pollutants ◽  
Uv Light ◽  
High Surface ◽  
High Surface Area ◽  
Thermal Conversion ◽  
Hybrid Nanostructures ◽  
Dipping Process ◽  
Porous Nanocomposites

An innovative approach for the fabrication of hybrid photocatalysts on a solid porous polymeric system for the heterogeneous photocatalytic degradation of organic pollutants is herein presented. Specifically, gold/zinc oxide (Au/ZnO)-based porous nanocomposites are formed in situ by a two-step process. In the first step, branched ZnO nanostructures fixed on poly(methyl methacrylate) (PMMA) fibers are obtained upon the thermal conversion of zinc acetate-loaded PMMA electrospun mats. Subsequently, Au nanoparticles (NPs) are directly formed on the surface of the ZnO through an adsorption dipping process and thermal treatment. The effect of different concentrations of the Au ion solutions to the formation of Au/ZnO hybrids is investigated, proving that for 1 wt % of Au NPs with respect to the composite there is an effective metal–semiconductor interfacial interaction. As a result, a significant improvement of the photocatalytic performance of the ZnO/PMMA electrospun nanocomposite for the degradation of methylene blue (MB) and bisphenol A (BPA) under UV light is observed. Therefore, the proposed method can be used to prepare flexible fibrous composites characterized by a high surface area, flexibility, and light weight. These can be used for heterogeneous photocatalytic applications in water treatment, without the need of post treatment steps for their removal from the treated water which may restrict their wide applicability and cause secondary pollution.

Photocatalytic Degradation of Acetaldehyde by Sol-Gel TiO2 Nanoparticles: Effect of the Physicochemical Properties on the Photocatalytic Activity

2011 ◽  
Vol 691 ◽  
pp. 92-98 ◽  
Author(s):  
R. Carrera ◽  
A.L. Vázquez ◽  
S. Castillo ◽  
E.M. Arce Estrada
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Surface Area ◽  
Photocatalytic Oxidation ◽  
Crystal Size ◽  
Uv Light ◽  
High Surface ◽  
Sol Gel ◽  
High Surface Area ◽  
Synthesis Method

Nowadays, nanostructured semiconductor materials offer promising opportunities for a new generation of materials such as TiO2nanoparticles with improved properties for their application in the environmental catalysis field. It is well known that the phocatalytic activity of the TiO2nanoparticles is strongly dependent on the surface area, crystal size, phase composition and synthesis method. Thus, the preparation conditions clearly affect the photocatalytic activity of the TiO2nanoparticles. This work deals with the study of the structure of TiO2nanoparticles that were synthesized by the sol-gel method (using isopropanol as solvent), and calcined at 200 and 500°C. The obtained samples were characterized by the XRD-Rietveld refinement, BET and TEM techniques; and tested in the photodecomposition of acetaldehyde. The evaluations were carried out at room temperature by using CH3CHO (300 ppmv), O2(2.0 %) in helium balance in a quartz glass photoreactor (gas phase) with a 365-UV light lamp. According to the results, the sample that presented the highest activity in the photocatalytic oxidation of acetaldehyde (96.4%) was the one annealed at 200 °C. This sample showed the following proportion of phases: anatase (62.88%) with a tetragonal structure (a=0.3790926, b=0.3790926, c=0.9495732) nm; and b) brookite (37.12%) with an orthorhombic structure (a=0.9167624, b=0.5416461, c=0.5210546) nm. The surface area was 189 m2/g and the average crystal size was 7.03 nm. From the results, it can be seen that this material showed high activity in the photocatalytic degradation of acetaldehyde because of: the presence of a mixture of the anatase (higher proportion) and brookite phases, nanometric crystal size and high surface area obtained in this TiO2material. According to the aforementioned, this material can be considered as a good option for the decomposition of acetaldehyde and other volatile organic compounds (VOCs) in confined spaces.

scholarly journals 2D SnS2 Nanostructure-Derived Photocatalytic Degradation of Organic Pollutants Under Visible Light

2021 ◽  
Vol 3 ◽  
Author(s):  
Rohit Ranjan Srivastava ◽  
Pramod Kumar Vishwakarma ◽  
Umakant Yadav ◽  
Suyash Rai ◽  
Sima Umrao ◽  
...  
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Organic Pollutants ◽  
Textile Industry ◽  
High Surface ◽  
High Surface Area ◽  
Methyl Violet ◽  
Kinetic Rate Constant ◽  
Xps Spectra

Wastewater produced by the textile industry contains various dyes and organic compounds that directly or indirectly affect surface water or groundwater pollution. Visible-light-driven semiconductor photocatalysis is the leading pathway for the degradation of environmental pollutants. Herein we report the bottom-up hydrothermal growth of 2D tin disulfide nanostructures (SnS2 NSs) for the efficient photodegradation of organic pollutants such as Rhodamine B (Rh.B) and Methyl Violet (M.V) in an aqueous medium under visible light (λ > 400 nm) irradiation. The as-synthesized SnS2 NSs were characterized by various structural, morphological, and optical techniques such as XRD, RAMAN, TEM, UV–Vis, Brunauer–Emmett–Teller, etc. Furthermore, the low bandgap (∼1.6 eV), the high surface area (56 m2/g), and the anionic nature of SnS2 NSs attribute to it as an efficient photocatalyst for photocatalytic applications. The photocatalytic properties of SnS2 NSs showed good degradation efficiency of 94 and 99.6% for Rh. B and M.V, respectively, in 25 min. The kinetic rate constant of these dyes was estimated by using the Langmuir–Hinshelwood model. Here we also performed the recyclability test of the photocatalyst and discussed the plausible mechanism for the photocatalytic degradation of organic pollutants. The XPS spectra of SnS2 NSs were studied before and after the photodegradation of Rh.B and M.V, indicating the high stability of the photocatalyst. Moreover, in vitro cytotoxicity was also evaluated against human cervical cancer cell lines (HeLa cells) with different concentrations (0–1,000 μg/ml) of as-synthesized SnS2 NSs. This intended work provides a possible treatment for the degradation of organic pollutants under visible light to balance the aquatic ecosystems.

Cu2O–TiO2 Composite for Photocatalytic Degradation of Benzene and its derivatives Using Visible Light

2021 ◽  
Vol 17 ◽  
Author(s):  
Satya Vijaya Kumar Nune ◽  
Ravi Kumar Golimidi
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Band Gap ◽  
Tio2 Nanoparticles ◽  
Uv Light ◽  
High Surface ◽  
High Surface Area ◽  
Visible Region ◽  
Copper Ion ◽  
Visible Light Active

Background: Heterostructured nanocomposites have gained huge attention for their catalytic properties lately. A wide array of different visible-light-active photocatalysts (VLAPs) have been extensively studied of the past couple of years to fine tune the band gap of various stable semiconductors. Objective: The current investigation reports the sensitization of TiO2 nanoparticles with nano sized cuprous oxide, a wellstudied p-type semiconductor, which has a relatively narrow band gap ranging between 2.1 eV & 2.6 eV, to obtain a visible light active photocatalyst. Methods: visible-light-active Cu2O–TiO2 nanocomposite synthesized using solvo-thermal technique. The nanocomposite’s structure and size properties were studied using powder diffraction (XRD), electron microscopy (FESEM and HRTEM). Cu2O–TiO2 nanocomposite was tested on benzene, toluene and chlorobenzene in contaminated water, under UV and under visible light, for effective implementation in photocatalytic degradation of volatile organic contaminants. Results: The said nanocomposite was crystalline and found to be 40–50 nm in size. No apparent change in the crystal lattice of TiO2 was observed due to the introduction of copper ion, and the nanocomposite also retained high surface area of 76.28 m2 /g. The efficiency of the Cu2O-TiO2 nanoparticles degradation is studied both under UV light and under visible. Cu2O-TiO2 nanoparticles have achieved 97 – 99% degradation of benzene, 92 – 97% degradation of toluene and 95 – 98% degradation of chlorobenzene in water. Conclusion: The said Cu2O–TiO2 nanocomposite is photo-active and showed an overall 95% degradation within 2 hours of treatment under the visible region.

In-situ Mössbauer effect spectroscopy of adsorbed species on high surface area electrodes

1982 ◽  
Vol 10 (3) ◽  
pp. 325-332 ◽  
Author(s):  
D. Scherson ◽  
S.B. Yao ◽  
E.B. Yeager ◽  
J. Eldridge ◽  
M.E. Kordesch ◽  
...  
Keyword(s):  
Surface Area ◽  
Mössbauer Effect ◽  
High Surface ◽  
High Surface Area ◽  
Mossbauer Effect ◽  
Adsorbed Species ◽  
Mössbauer Effect Spectroscopy

Large-scale synthesis of Au–WO3 porous hollow spheres and their photocatalytic properties

2017 ◽  
Vol 7 (17) ◽  
pp. 3702-3706 ◽  
Author(s):  
Chenying He ◽  
Xia Li ◽  
Yahui Li ◽  
Junfang Li ◽  
Guangcheng Xi
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Organic Pollutants ◽  
Hybrid Materials ◽  
Large Scale ◽  
Hollow Spheres ◽  
Photocatalytic Properties ◽  
Excellent Activity ◽  
Visible Light Photocatalytic

Uniform Au–WO3 porous hollow spheres have been synthesized on a large-scale by a general in situ reaction. The hybrid materials exhibit excellent activity for visible-light photocatalytic degradation of organic pollutants.

High Surface Area SnO2 -Ta2 O5 Composite for Visible Light-driven Photocatalytic Degradation of an Organic Dye

2018 ◽  
Vol 94 (4) ◽  
pp. 633-640 ◽  
Author(s):  
Bharath Velaga ◽  
Pradeep P. Shanbogh ◽  
Diptikanta Swain ◽  
Chandrabhas Narayana ◽  
Nalini G. Sundaram
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Organic Dye ◽  
Visible Light Driven

scholarly journals The synthesis of a BiOClxBr1−x nanostructure photocatalyst with high surface area for the enhanced visible-light photocatalytic reduction of Cr(vi)

RSC Advances ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 4763-4771 ◽  
Author(s):  
Muhammad Bilal Hussain ◽  
Malik Saddam Khan ◽  
Herman Maloko Loussala ◽  
Muhammad Sohail Bashir
Keyword(s):  
Visible Light ◽  
Surface Area ◽  
Room Temperature ◽  
High Surface ◽  
High Surface Area ◽  
Photocatalytic Reduction ◽  
Synthetic Process ◽  
Visible Light Photocatalytic

Cr(vi) reduction is performed by BiOCl0.8Br0.2 composite produced via a facile in situ synthetic process at room temperature while making use of PVP (Mw = 10 000).

Sign in / Sign up

Export Citation Format

Share Document