Enhanced sunlight-driven photocatalytic activity of SnO2-Sb2O3 composite towards emerging contaminant degradation in water

2021 ◽  
pp. 162935
Author(s):  
D. Rani Rosaline ◽  
A. Suganthi ◽  
G. Vinodhkumar ◽  
S.S.R. Inbanathan ◽  
Ahmad Umar ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Emerging Contaminant ◽  
Contaminant Degradation

scholarly journals Mesoporous Metal-Containing Carbon Nitrides for Improved Photocatalytic Activities

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Jie Luo ◽  
Zhao-Jie Cui ◽  
Guo-Long Zang
Keyword(s):  
Photocatalytic Activity ◽  
Mesoporous Structure ◽  
Hard Template ◽  
Visible Absorption ◽  
Contaminant Degradation ◽  
Photocatalytic Activities ◽  
Carbon Nitrides ◽  
Uv Visible ◽  
Mesoporous Metal ◽  
Positive Effect

Graphitic carbon nitrides (g-C3N4) have attracted increasing interest due to their unusual properties and promising applications in water splitting, heterogeneous catalysis, and organic contaminant degradation. In this study, a new method was developed for the synthesis of mesoporous Fe contained g-C3N4(m-Fe-C3N4) photocatalyst by using SiO2nanoparticles as hard template and dicyandiamide as precursor. The physicochemical properties of m-Fe-C3N4were thoroughly investigated. The XRD and XPS results indicated that Fe was strongly coordinated with the g-C3N4matrix and that the doping and mesoporous structure partially deteriorated its crystalline structure. The UV-visible absorption spectra revealed that m-Fe-C3N4with a unique electronic structure displays an increased band gap in combination with a slightly reduced absorbance, implying that mesoporous structure modified the electronic properties of g-Fe-C3N4. The photocatalytic activity of m-Fe-C3N4for photodegradation of Rhodamine B (RhB) was much higher than that of g-Fe-C3N4, clearly demonstrating porous structure positive effect.

scholarly journals TiO2-Doped Electrospun Nanofibrous Membrane for Photocatalytic Water Treatment

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 747 ◽  
Author(s):  
Miren Blanco ◽  
Cristina Monteserín ◽  
Adrián Angulo ◽  
Ana Pérez-Márquez ◽  
Jon Maudes ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Photocatalytic Activity ◽  
Uv Light ◽  
Titanium Dioxide Nanoparticles ◽  
Polyamide 6 ◽  
Coliform Bacteria ◽  
Polluted Water ◽  
Contaminant Degradation ◽  
Immobilized Catalyst ◽  
The One

This work has been focused on the one-step fabrication by electrospinning of polyamide 6 (PA6) nanofibre membranes modified with titanium dioxide nanoparticles (TiO2), where these TiO2 nanoparticles aggregates could induce a photocatalytic activity. The main potential application of these membranes could be the purification of contaminated water. Thus, it is important to analyse the contaminant degradation capability since in these membranes this is based on their photocatalytic activity. In this work, the effect of the photocatalysis has been studied both on the degradation of an organic model contaminant and on the removal of Escherichia coli and other coliform bacteria. As a result, it was observed that these membranes present excellent photocatalytic activity when they are irradiated under UV light, allowing a 70% reduction of an organic model pollutant after 240 min. In addition, these membranes successfully removed Escherichia coli and other coliform bacteria in artificially inoculated water after 24 h of contact with them. Moreover, the stand-alone structure of the membranes allowed for the reusing of the immobilized catalyst. The experimental evidence indicated that developed nanofibre membranes are a fast and efficient solution for polluted water decontamination based on photocatalysis. Their use could contribute to guarantee a fresh water level and quality, mitigating the water scarcity problem worldwide.

scholarly journals Synthesis of N/Fe Comodified TiO2Loaded on Bentonite for Enhanced Photocatalytic Activity under UV-Vis Light

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Xi Cao ◽  
Chen Liu ◽  
Yandi Hu ◽  
Wenli Yang ◽  
Jiawei Chen
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Sol Gel ◽  
Visible Region ◽  
Nitrogen Adsorption ◽  
Single Element ◽  
Photocatalytic Efficiency ◽  
Paramagnetic Resonance ◽  
X Ray ◽  
Contaminant Degradation

To improve the efficiency of TiO2as a photocatalyst for contaminant degradation, a novel nanocomposite catalyst of (N, Fe) modified TiO2nanoparticles loaded on bentonite (B-N/Fe-TiO2) was successfully prepared for the first time by sol-gel method. The synthesized B-N/Fe-TiO2catalyst composites were characterized by multiple techniques, including scanning electron microscope (SEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), X-ray fluorescence (XRF), nitrogen adsorption/desorption, UV-Vis diffuse reflectance spectra (DRS), and electron paramagnetic resonance (EPR). The results showed that bentonite significantly enhanced the dispersion of TiO2nanoparticles and increased the specific surface area of the catalysts. Compared with nondoped TiO2, single element doped TiO2, or unloaded TiO2nanoparticles, B-N/Fe-TiO2had the highest absorption in UV-visible region. The photocatalytic activity of B-N/Fe-TiO2was also the highest, based on the degradation of methyl blue (MB) at room temperature under UV and visible light irradiation. In particular, the synthesized B-N/Fe-TiO2showed much greater photocatalytic efficiency than N/Fe-TiO2under visible light, the newly synthesized B-N/Fe-TiO2is going to significantly increase the photocatalytic efficiency of the catalyst using sun light.

Photocatalytic degradation of methylene blue from aqueous solutions using nanopillars-TiO2 thin films: Batch reactor studies

2018 ◽  
Vol 18 (3) ◽  
pp. 81-91 ◽  
Author(s):  
C. Lalhriatpuia
Keyword(s):  
Thin Films ◽  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Organic Carbon ◽  
Photocatalytic Degradation ◽  
Batch Reactor ◽  
Tio2 Thin Films ◽  
Initial Concentration ◽  
Bet Specific Surface Area ◽  
Interfering Ions

Nanopillars-TiO2 thin films was obtained on a borosilicate glass substrate with (S1) and without (S2) polyethylene glycol as template. The photocatalytic behaviour of S1 and S2 thin films was assessed inthe degradation of methylene blue (MB) dye from aqueous solution under batch reactor operations. The thin films were characterized by the SEM, XRD, FTIR and AFM analytical methods. BET specific surface area and pore sizes were also obtained. The XRD data confirmed that the TiO2 particles are in its anatase mineral phase. The SEM and AFM images indicated the catalyst is composed with nanosized pillars of TiO2, evenly distributed on the surface of the substrate. The BET specific surface area and pore sizes of S1 and S2 catalyst were found to be 5.217 and 1.420 m2/g and 7.77 and 4.16 nm respectively. The photocatalytic degradation of MB was well studied at wide range of physico-chemical parameters. The effect of solution pH (pH 4.0 to 10.0) and MB initial concentration (1.0 to 10.0 mg/L) was extensively studied and the effect of several interfering ions, i.e., cadmium nitrate, copper sulfate, zinc chloride, sodium chloride, sodium nitrate, sodium nitrite, glycine, oxalic acid and EDTA in the photocatalytic degradation of MB was demonstrated. The maximum percent removal of MB was observed at pH 8.0 beyond which it started decreasing and a low initial concentration of the pollutant highly favoured the photocatalytic degradation using thin films and the presence of several interfering ions diminished the photocatalytic activity of thin films to some extent. The overall photocatalytic activity was in the order: S2 > S1 > UV. The photocatalytic degradation of MB was followed the pseudo-first-order rate kinetics. The mineralization of MB was studied with total organic carbon measurement using the TOC (total organic carbon) analysis.

Photocatalytic activity of TiO2 synthesized by anodization and anodic spark deposition

MRS Advances ◽  
2020 ◽  
Vol 5 (61) ◽  
pp. 3141-3152
Author(s):  
Alma C. Chávez-Mejía ◽  
Génesis Villegas-Suárez ◽  
Paloma I. Zaragoza-Sánchez ◽  
Rafael Magaña-López ◽  
Julio C. Morales-Mejía ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Surface Characteristics ◽  
Amorphous Solids ◽  
X Ray Diffraction ◽  
X Ray ◽  
Catalytic Activities ◽  
Anodic Spark Oxidation ◽  
Porous Surfaces ◽  
Scanning Electron

AbstractSeveral photocatalysts, based on titanium dioxide, were synthesized by spark anodization techniques and anodic spark oxidation. Photocatalytic activity was determined by methylene blue oxidation and the catalytic activities of the catalysts were evaluated after 70 hours of reaction. Scanning Electron Microscopy and X Ray Diffraction analysis were used to characterize the catalysts. The photocatalyst prepared with a solution of sulfuric acid and 100 V presented the best performance in terms of oxidation of the dye (62%). The electric potential during the synthesis (10 V, low potential; 100 V, high potential) affected the surface characteristics: under low potential, catalyst presented smooth and homogeneous surfaces with spots (high TiO2 concentration) of amorphous solids; under low potential, catalyst presented porous surfaces with crystalline solids homogeneously distributed.

Impact of Rutile Fraction on TiO2 Visible-Light Absorption and Visible-Light-Induced Photocatalytic Activity

2018 ◽  
Author(s):  
David Maria Tobaldi ◽  
Luc Lajaunie ◽  
ana caetano ◽  
nejc rozman ◽  
Maria Paula Seabra ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Light Absorption ◽  
Solid Phase ◽  
Diffraction Method ◽  
Band Alignment ◽  
Quantitative Phase Analysis ◽  
Transmission Microscopy ◽  
Visible Light Absorption ◽  
X Ray

<div>Titanium dioxide is by far the most utilised semiconductor material for photocatalytic applications. Still, it is transparent to visible-light. Recently, it has been proved that a type-II band alignment for the rutile−anatase mixture would improve its visible-light absorption.</div><div>In this research paper we thoroughly characterised the real crystalline and amorphous phases of synthesised titanias – thermally treated at different temperatures to get distinct ratios of anatase-rutile-amorphous fraction – as well as that of three commercially available photocatalytic nano-TiO2. </div><div>The structural characterisation was done via advanced X-ray diffraction method, namely the Rietveld-RIR method, to attain a full quantitative phase analysis of the specimens. The microstructure was also investigated via an advanced X-ray method, the whole powder pattern modelling. These methods were validated combining advanced aberration-corrected scanning transmission microscopy and high-resolution electron energy-loss spectroscopy. The photocatalytic activity was assessed in the liquid- and gas-solid phase (employing rhodamine B and 4-chlorophenol, and isopropanol, respectively, as the organic substances to degrade) using a light source irradiating exclusively in the visible-range.</div><div>Optical spectroscopy showed that even a small fraction of rutile (2 wt%) is able to shift to lower energies the apparent optical band gap of an anatase-rutile mixed phase. But is this enough to attain a real photocatalytic activity promoted by merely visible-light?</div><div>We tried to give a reply to that question.</div><div>Photocatalytic activity results in the liquid-solid phase showed that a high surface hydroxylation led to specimen with superior visible light-induced catalytic activity (i.e. dye and ligand-to-metal charge transfer complexes sensitisation effects). That is: not photocatalysis <i>sensu-strictu</i>.</div><div>On the other hand, the gas-solid phase results showed that a higher amount of the rutile fraction (around 10 wt%), together with less recombination of the charge carriers, were more effective for an actual photocatalytic oxidation of isopropanol.</div>

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