scholarly journals Photocatalytic Degradation of Ethiofencarb by a Visible Light-Driven SnIn4S8 Photocatalyst

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1325
Author(s):  
Chiing-Chang Chen ◽  
Janah Shaya ◽  
Kyriaki Polychronopoulou ◽  
Vladimir B. Golovko ◽  
Siriluck Tesana ◽  
...  
Keyword(s):  
Visible Light ◽  
Catalytic Efficiency ◽  
Degradation Process ◽  
Active Species ◽  
Operating Conditions ◽  
Gas Chromatography Mass Spectrometry ◽  
Oh Radicals ◽  
Amide Bonds ◽  
Electronic Spin ◽  
Visible Light Driven

This work reports the preparation and detailed characterization of stannum indium sulfide (SnIn4S8) semiconductor photocatalyst for degradation of ethiofencarb (toxic insecticide) under visible-light irradiation. The as-prepared SnIn4S8 showed catalytic efficiency of 98% in 24 h under optimal operating conditions (pH = 3, catalyst dosage of 0.5 g L−1). The photodegradation reaction followed pseudo-first-order kinetics. The major intermediates have been identified using gas chromatography/mass spectrometry. •O2− and •OH radicals appeared to be the primary active species in the degradation process as revealed by scavenger and electronic spin resonance studies, while photogenerated holes had a secondary role in this process. A plausible mechanism involving two routes was proposed for ethiofencarb degradation by SnIn4S8 after identifying the major intermediate species: oxidative cleavage of the CH2-S and the amide bonds of the carbamate moiety. Lastly, SnIn4S8 was found to be efficient, stable, and reusable in treating real water samples in three successive photodegradation experiments. This study demonstrates the prospect of SnIn4S8 photocatalysis in treatment of natural and contaminated water from extremely toxic organic carbamates as ethiofencarb.

scholarly journals Ionic Liquid-Assisted Synthesis of Ag3PO4 Spheres for Boosting Photodegradation Activity under Visible Light

Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 788
Author(s):  
Beibei Zhang ◽  
Lu Zhang ◽  
Yulong Zhang ◽  
Chao Liu ◽  
Jiexiang Xia ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Visible Light ◽  
High Efficiency ◽  
Chemical Precipitation ◽  
Active Species ◽  
Precipitation Method ◽  
Dihydrogen Phosphate ◽  
Xrd Pattern ◽  
Simple Chemical ◽  
Visible Light Driven

In this work, a simple chemical precipitation method was employed to prepare spherical-like Ag3PO4 material (IL-Ag3PO4) with exposed {111} facet in the presence of reactive ionic liquid 1-butyl-3-methylimidazole dihydrogen phosphate ([Omim]H2PO4). The crystal structure, microstructure, optical properties, and visible-light photocatalytic performance of as-prepared materials were studied in detail. The addition of ionic liquids played a crucial role in forming spherical-like morphology of IL-Ag3PO4 sample. Compared with traditional Ag3PO4 material, the intensity ratio of {222}/{200} facets in XRD pattern of IL-Ag3PO4 was significantly enhanced, indicating the main {111} facets exposed on the surface of IL-Ag3PO4 sample. The presence of exposed {111} facet was advantageous for facilitating the charge carrier transfer and separation. The light-harvesting capacity of IL-Ag3PO4 was larger than that of Ag3PO4. The photocatalytic activity of samples was evaluated by degrading rhodamine B (RhB) and p-chlorophenol (4-CP) under visible light. The photodegradation efficiencies of IL-Ag3PO4 were 1.94 and 2.45 times higher than that of Ag3PO4 for RhB and 4-CP removal, respectively, attributing to a synergy from the exposed {111} facet and enhanced photoabsorption. Based on active species capturing experiments, holes (h+), and superoxide radical (•O2−) were the main active species for visible-light-driven RhB photodegradation. This study will provide a promising prospect for designing and synthesizing ionic liquid-assisted photocatalysts with a high efficiency.

Tetracycline Removal Enhancement With Fe-Saturated Nanoporous Montmorillonite in a Tripartite Adsorption/Desorption/Photo-Fenton Degradation Process

2021 ◽  
Author(s):  
Shiva Chahardahmasoumi ◽  
Seyed Amir Hossein Jalali ◽  
Mehdi Nasiri Sarvi
Keyword(s):  
Antimicrobial Activity ◽  
Visible Light ◽  
Fenton Reaction ◽  
Degradation Process ◽  
Oh Radicals ◽  
Desorption Process ◽  
High Tc ◽  
Modified Montmorillonite ◽  
Adsorption Desorption ◽  
First Time

Abstract The adsorption and photo-Fenton degradation of tetracycline (TC) over Fe saturated nanoporous montmorillonite was analyzed. The synthesized samples were characterized using XRD, FTIR, SEM, and XRF analysis, and the adsorption and desorption of TC onto these samples as well as the antimicrobial activity of TC during these processes were analyzed at different pH. The results indicated that the montmorillonite is a great adsorbent for the separation of the TC from aqueous solutions, however, after increasing the amount of TC adsorbed, the desorption process started, and up to 50% of TC adsorbed onto non-modified montmorillonite was released back to the solution with almost no changes in its antimicrobial activity. After acid treatment (for creation of nanoporous layers) and Fe saturation of the montmorillonite, almost similar great separation was achieved compared to non-modified montmorillonite. In addition, the desorption of TC from modified montmorillonite was still high up to 40% of adsorbed TC. However, simultaneous adsorption and photodegradation of TC were detected and almost no antimicrobial activity was detected after 180 min of visible light irradiation, which could be due to the photo-Fenton degradation of TC on the modified montmorillonite surface. In the porous structures of modified montmorillonite high ˙OH radicals were created in the photo-Fenton reaction and were measured using the Coumarin technique. The ˙OH radicals help the degradation of TC as proposed in an oxidation process. Surprisingly, more than 90 % of antimicrobial activity of the TC decreased under visible light (after 180 min) when desorbed from nanoporous Fe-saturated montmorillonite compared to natural montmorillonite. To the best of our knowledge, this is the first time that such a high TC desorption rate from an adsorbent with the least remained antimicrobial activity is reported which makes nanoporous Fe-saturated montmorillonite a perfect separation substance of TC from the environment.

In situ synthesis of hierarchical nitrogen-doped MoS2 microsphere with an excellent visible light-driven photocatalytic nitrogen fixation ability

2020 ◽  
Vol 13 (05) ◽  
pp. 2051031
Author(s):  
Abulikemu Abulizi ◽  
Hujiabudula Maimaitizi ◽  
Dilinuer Talifu ◽  
Yalkunjan Tursun
Keyword(s):  
Visible Light ◽  
High Performance ◽  
Nucleation Site ◽  
Active Species ◽  
Nitrogen Doped ◽  
Photogenerated Electrons ◽  
The Hierarchical Structure ◽  
Visible Light Driven

A photocatalyst of high-performance hierarchical nitrogen-doped MoS2 (N-MoS2) microsphere was fabricated by an in situ hydrothermal method in the presence of cetyltrimethylammonium bromide (CTAB). The as-prepared N-MoS2 microsphere was self-assembled by extremely thin interleaving petals, where CTAB acts as a nucleation site for the formation of the interleaving petals due to the strong interaction between CTA+ and [Formula: see text]. N-MoS2 showed higher N2 fixation ability (101.2 [Formula: see text] mol/g(cat)h) than the non-doped MoS2 under the visible light irradiation, and the improved photocatalytic activity could be ascribed to that the doped N narrows the band gap, and the surface reflecting and scattering effect caused by the hierarchical structure enhance the light adsorption. The trapping experiment of active species was also investigated to evaluate the role of photogenerated electrons in the photocatalytic reaction process. Meanwhile, the possible mechanism for the formation and excellent photocatalytic performance of N-MoS2 microsphere were also presented.

scholarly journals Visible-Light-Driven Photocatalytic Activity of Magnetic BiOBr/SrFe12O19 Nanosheets

Nanomaterials ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 735 ◽  
Author(s):  
Taiping Xie ◽  
Jiao Hu ◽  
Jun Yang ◽  
Chenglun Liu ◽  
Longjun Xu ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Electron Microscope ◽  
Visible Light ◽  
Uv Light ◽  
Light Emitting Diode ◽  
Active Species ◽  
Composite Catalyst ◽  
Light Emitting ◽  
Transmission Electron ◽  
Visible Light Driven

Magnetic BiOBr/SrFe12O19 nanosheets were successfully synthesized using the hydrothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and UV-visible diffused reflectance spectra (UV-DRS), and the magnetic properties were tested using a vibration sample magnetometer (VSM). The as-produced composite with an irregular flaky-shaped aggregate possesses a good anti-demagnetization ability (Hc = 861.04 G) and a high photocatalytic efficiency. Under visible light (λ > 420 nm) and UV light-emitting diode (LED) irradiation, the photodegradation rates of Rhodamine B (RhB) using BiOBr/SrFe12O19 (5 wt %) (BOB/SFO-5) after 30 min of reaction were 97% and 98%, respectively, which were higher than that using BiOBr (87%). The degradation rate of RhB using the recovered BiOBr/5 wt % SrFe12O19 (marked as BOB/SFO-5) was still more than 85% in the fifth cycle, indicating the high stability of the composite catalyst. Meanwhile, after five cycles, the magnetic properties were still as stable as before. The radical-capture experiments proved that superoxide radicals and holes were main active species in the photocatalytic degradation of RhB.

scholarly journals CuInS2/Mg(OH)2 Nanosheets for the Enhanced Visible-Light Photocatalytic Degradation of Tetracycline

Nanomaterials ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1567 ◽  
Author(s):  
Xiaogang Zheng ◽  
Yiting Mao ◽  
Jing Wen ◽  
Xiaojin Fu ◽  
Xinhui Liu
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Ph Value ◽  
Inorganic Ions ◽  
Charge Carriers ◽  
Oh Radicals ◽  
Cycle Times ◽  
Atomic Force ◽  
Excellent Photocatalytic Activity ◽  
Visible Light Driven

CuInS2/Mg(OH)2 (CIS/Mg(OH)2) nanosheets have been prepared for the visible light activated photodegradation of tetracycline hydrochloride (TCH). The introduction of CuInS2 has proven to enhance the photocatalytic activity of Mg(OH)2 nanosheets. It’s ascribed to the enhanced transfer and separation of charge carriers at the junction interface between CuInS2 and Mg(OH)2. The photocatalytic activity of obtained CIS/Mg(OH)2 is greatly affected by CuInS2 content, pH value, and inorganic ions. Among these samples, 2-CIS/Mg(OH)2 exhibits the excellent photocatalytic activity and durability for the visible light driven removal of TCH after five cycle times. Atomic force microscope (AFM) images indicate that the surface roughness of 2-CIS/Mg(OH)2 is intensively influenced in adsorption-photocatalysis process. The •O2− and •OH radicals are vital for the visible light driven photocatalytic activity of 2-CIS/Mg(OH)2 for TCH removal.

Photodegradation Studies on Orange G and Acid Blue 113: New Doped Rare Earth Nanometal Oxides as Visible Light Active Photo Catalyst

2014 ◽  
Vol 938 ◽  
pp. 257-262
Author(s):  
G.A. Suganya Josephine ◽  
Arumugam Sivasamy
Keyword(s):  
Rare Earth ◽  
Visible Light ◽  
Kinetic Studies ◽  
Degradation Process ◽  
Oh Radicals ◽  
Time Duration ◽  
Ph Variation ◽  
Orange G ◽  
Acid Blue 113 ◽  
Acid Blue

Dyes are a source of serious pollutants from different industrial outlets and show a major contribution in polluting the environment. In the present study two dyes namely Orange G and Acid Blue 113 were compared for their photodegradation efficiency employing rare earth nanometal oxide as a visible active photocatalyst. The prepared catalyst was nanocrystalline form with particle size 70 nm and the surface of the catalyst was highly porous and rough which facilitates the absorption of the dye further enhance the photo degradation which were confirmed by various characterization techniques. Effect of pH, variation of catalyst dosage, variation of initial dye concentration and kinetic studies were conducted for both the dyes. The reaction followed a pseudo first order kinetics. The activity of the prepared catalyst was higher when compared to a commercially used metal oxide. Reusability studies proved that the catalyst prepared was very active even upto the third cycle. The degradation process was initiated by the attack of the OH radical generated in the in-situ process via visible light irradiation. EPR spin trapping technique was employed to confirm the presence of OH radicals. The prepared catalyst degraded the dye molecules of interest in lesser time duration by absorption of visible light, thereby reducing the cost of photodegradation.

Synthesis and Characterization of WO3and#183;0.33H2O/Ag2MoO4 Composites as a Visible-Light-Driven Photocatalyst for Rhodamine B and Levofloxacin Degradation

2020 ◽  
Vol 42 (6) ◽  
pp. 827-827
Author(s):  
Yun Xuan Fu Yun Xuan Fu ◽  
Yan Li Yan Li ◽  
Tian Long Chang Tian Long Chang ◽  
Xu Tao Liu Xu Tao Liu ◽  
Xiang Feng Wu Xiang Feng Wu ◽  
...  
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Rhodamine B ◽  
Organic Dyes ◽  
Degradation Process ◽  
Molar Ratio ◽  
Leading Role ◽  
Visible Light Driven

Visible-light-driven WO3and#183;0.33H2O/Ag2MoO4 composites have been prepared by using an in-situ growth of Ag2MoO4 nanoparticles on the surfaces of WO3and#183;0.33H2O. The photocatalytic activities of the samples were studied by degradation of rhodamine B and levofloxacin dilute solution. The synergistic photocatalytic mechanism was also analyzed. Experimental results reveal that the as-developed hybrids have higher photocatalytic activity than pure samples. When the theoretical molar ratio of WO3and#183;0.33H2O to Na2MoO4and#183;2H2O is 1:0.15, the as-developed hybrids have the highest photocatalytic degradation efficiency of 99.0% for rhodamine B in 45 min and 40.9% for levofloxacin in 120 min. Furthermore, there are chemical bonds between WO3and#183;0.33H2O and Ag2MoO4. In addition, the super oxide radicals play the leading role during the photocatalytic degradation process of the samples. This work will provide reference for treatment of organic dyes and antibiotics pollution in water with using solar energy.

In Situ Fabrication of TiO2/Bi3.64Mo0.36O6.55Nanocomposite with High Visible-Light-Driven Photocatalytic Efficiency

NANO ◽  
2017 ◽  
Vol 12 (05) ◽  
pp. 1750059 ◽  
Author(s):  
Zhiyuan Yang ◽  
Junjie Wang ◽  
Lu Chen ◽  
Mengjun Liang ◽  
Yulin Xu ◽  
...  
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Diffuse Reflectance Spectroscopy ◽  
Active Species ◽  
Light Irradiation ◽  
Cycle Performance ◽  
X Ray Diffraction ◽  
In Situ Fabrication ◽  
Transmission Electron ◽  
Visible Light Driven

In this work, we developed a simple hydrothermal method toward the fabrication of TiO2/Bi[Formula: see text]Mo[Formula: see text]O[Formula: see text] heterostructure, which had superior photocatalytic performance for degrading of RhB under visible light irradiation. The as-prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), high-resolution transmission electron microscopy (HRTEM), UV-Vis diffuse reflectance spectroscopy (DRS) and photoelectrochemical measurements. The optimal composite with 15[Formula: see text]wt.% TiO2/Bi[Formula: see text]Mo[Formula: see text]O[Formula: see text] (TBMO3) exhibits a much higher photocatalytic activity than that of Bi[Formula: see text]Mo[Formula: see text]O[Formula: see text] and P25 by degradation of RhB under visible light irradiation within 20[Formula: see text]min. The enhanced performance of TBMO3 is predominantly attributed to the synergistic effect both in the higher surface area and the improved separation of photogenerated charge carriers between the two semiconductors. Recycling experiments indicated that TiO2/Bi[Formula: see text]Mo[Formula: see text]O[Formula: see text] photocatalysts had excellent cycle performance and stability. The photocatalytic mechanism of nanocomposite photocatalysts was proposed, which is confirmed by the active species trapping experiments and photoluminescence tests.

Environmental Friendly Degradation of Atrazine by Ozone and Identification of Main Degradation Products

2014 ◽  
Vol 1001 ◽  
pp. 52-57
Author(s):  
Marián Šudý ◽  
Karol Balog ◽  
Maroš Soldán
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Degradation Products ◽  
Degradation Process ◽  
Gas Chromatography Mass Spectrometry ◽  
Oh Radicals ◽  
Environmental Friendly ◽  
Chromatography Mass Spectrometry ◽  
Atrazine Degradation

The present study investigates the degradation of atrazine (2-chloro-4-(ethylamino)-6-isopropylamino-s-triazine) by ozone and OH radicals during ozonization with the identification of the main degradation products after ozonation. The identification of main degradation products during atrazine degradation process was conducted by gas chromatography–mass spectrometry (GC–MS).

scholarly journals Aqueous synthesis of Nb-modified SnO2 quantum dots for efficient photocatalytic degradation of polyethylene for in situ agricultural waste treatment

2021 ◽  
Vol 10 (1) ◽  
pp. 499-506
Author(s):  
Jia Shao ◽  
Kai Deng ◽  
Le Chen ◽  
Chaomeng Guo ◽  
Congshan Zhao ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Waste Treatment ◽  
Low Cost ◽  
Agricultural Waste ◽  
Degradation Process ◽  
Active Species ◽  
Aqueous Synthesis

Abstract Low density polyethylene is widely used in agricultural production. It is of low cost and able to significantly improve the quality of fruits. However, its decomposition under natural circumstances needs more than one hundred of years. If not removed in time, it is hazardous to the ecological environment and crops. Up to now, the removal techniques of polyethylene films are polluted, expensive, and difficult to employ. A novel method is proposed for in situ removal of polyethylene by an effective and environmental friendly technique with low cost. The Nb-modified SnO2 quantum dots are prepared for the efficient photocatalytic degradation of polyethylene under visible light. The green synthesis of the photocatalyst includes the procedures of hydrolysis, oxidation, and hydrothermal treatment in aqueous solution. The Nb-modified SnO2 has a band gap of 2.95 eV, which enhances its absorption of visible light. A degradation efficiency of 29% is obtained within 6 h under visible irradiation. The hydroxyl radicals (•OH) are main active species in the degradation process. The prepared Nb-SnO2 quantum dots demonstrate a promising application in the photocatalytic degradation of polyethylene, contributing a novel strategy for the in situ treatment of agricultural wastes.

Sign in / Sign up

Export Citation Format

Share Document