Mesoporous LaFeO3: Synergistic Effect of Adsorption and Visible Light Photo-Fenton Processes for Phenol Removal from Refinery Wastewater

Mesoporous LaFeO3 as a visible light-driven photocatalyst was prepared by a nanocasting method using mesoporous silica (SBA-15) as a hard template. The as-prepared LaFeO3 photocatalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS), and optical absorption spectra. The characterization studies and experimental results showed that LaFeO3 with porous structure caused by the removal of SBA-15 hard template could enhance the specific surface area of the resulting photocatalyst, which improves the phenol adsorption ability of the photocatalyst and in turn enhances its photo-Fenton catalytic activity. The photo-Fenton catalytic activity of the photocatalyst was investigated by photo-Fenton degradation of aqueous phenol under visible light irradiation. The effects of catalyst dosage, H2O2 concentration, and solution pH on the photo-Fenton catalytic degradation of phenol using mesoporous LaFeO3 were studied and optimized. Under the optimal conditions of 20 mg L−1 phenol, 1.0 g L−1 catalyst, and 10 mM H2O2 at pH = 5, the photo-Fenton degradation of phenol (93.47%) was achieved in 180 min under visible light irradiation. Furthermore, our results proved the stability and reusability of mesoporous LaFeO3 and revealed its catalytic mechanism for the photo-Fenton degradation of phenol.

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Photosensitization of Carbon Nitride Photoelectrodes with CdS: A Novel Architecture with Highly Efficient Photocatalytic Activity

International Journal of Photoenergy ◽

10.1155/2014/843873 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8

Author(s):

Xiaosong Zhou ◽

Fei Yang ◽

Bei Jin ◽

Tang Xu ◽

Yaqing Yang ◽

...

Keyword(s):

Electron Microscopy ◽

Catalytic Activity ◽

Visible Light ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

Carbon Nitride ◽

Light Irradiation ◽

Diffuse Reflection Spectroscopy ◽

X Ray ◽

Acid Orange Ii

CdS with well-defined crystallinity is anchored on carbon nitride photoelectrodes by a successive chemical bath deposition. And the as-synthesized samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, ultraviolet-visible diffuse reflection spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy techniques. The effect of the amount of CdS on the catalytic activity for the degradation of acid Orange II is investigated under visible light irradiation. Results show that the photoelectrodes composed of CdS/CN exhibit much higher catalytic activity than pure CN photoelectrodes. A possible photocatalytic mechanism of the CdS/CN electrodes is proposed under visible light irradiation.

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Photocatalytic degradation of deoxynivalenol over dendritic-like α-Fe2O3 under visible light irradiation

Toxins ◽

10.3390/toxins11020105 ◽

2019 ◽

Vol 11 (2) ◽

pp. 105 ◽

Cited By ~ 14

Author(s):

Huiting Wang ◽

Jin Mao ◽

Zhaowei Zhang ◽

Qi Zhang ◽

Liangxiao Zhang ◽

...

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Photocatalytic Degradation ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

High Performance ◽

Synthesis Method ◽

Light Irradiation ◽

Trichothecene Mycotoxin ◽

X Ray

Deoxynivalenol (DON) is a secondary metabolite produced by Fusarium, which is a trichothecene mycotoxin. As the main mycotoxin with high toxicity, wheat, barley, corn and their products are susceptible to contamination of DON. Due to the stability of this mycotoxin, traditional methods for DON reduction often require a strong oxidant, high temperature and high pressure with more energy consumption. Therefore, exploring green, efficient and environmentally friendly ways to degrade or reduce DON is a meaningful and challenging issue. Herein, a dendritic-like α-Fe2O3 was successfully prepared using a facile hydrothermal synthesis method at 160 °C, which was systematically characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). It was found that dendritic-like α-Fe2O3 showed superior activity for the photocatalytic degradation of DON in aqueous solution under visible light irradiation (λ > 420 nm) and 90.3% DON (initial concentration of 4.0 μg/mL) could be reduced in 2 h. Most of all, the main possible intermediate products were proposed through high performance liquid chromatography-mass spectrometry (HPLC-MS) after the photocatalytic treatment. This work not only provides a green and promising way to mitigate mycotoxin contamination but also may present useful information for future studies.

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Design and fabrication of Ag3VO4/g-C3N4 heterostructure photocatalyst for enhanced visible light degradation of various organic pollutants

10.21203/rs.3.rs-329610/v1 ◽

2021 ◽

Author(s):

N Sujatha ◽

M Meenachi ◽

S Mohammed Harshulkhanb ◽

H.H Hegazy

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Light Irradiation ◽

X Rays ◽

Hydrothermal Route ◽

X Ray ◽

Visible Light Degradation

Abstract In later years, numerous viable photocatalysts have been created in order to illuminate the issues of natural toxins. In this work, heterostructured photocatalysts Ag3VO4/g-C3N4 were prepared by effortless hydrothermal route in order to anchor Ag3VO4 on the surface of the g-C3N4 nanosheets. The prepared samples were fairly characterized using X-ray diffraction (XRD), Energy dispersive analysis of X-rays (EDAX), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy (UV-DRS), photoluminescence, and X-ray photoelectron spectroscopy (XPS) techniques. The photocatalytic activity of the samples was evaluated by degrading malachite green (MG) and 2,4 dimethyl phenol (DMP) in aqueous solution under visible light irradiation. Compared with Ag3VO4 and g-C3N4, the heterojuncted photocatalyst 50 wt% Ag3VO4/g-C3N4 exhibits the best activity such as high degradation efficiency (99%), high apparent constant (0.0923 min− 1) and long term stability towards DMP under visible light irradiation. The development of a phase scheme heterojunction between Ag3VO4 and g-C3N4 improved the photocatalytic efficiency of Ag3VO4/g-C3N4 composites. Furthermore, the porous structure of g-C3N4 and the effect of Ag surface plasmon resonance (SPR) speed up the isolation and transfer of electron-hole pairs, reducing the likelihood of recombination.

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Selective Oxidation of Benzyl Alcohol by Ag/Pd/m-BiVO4 Microspheres under Visible Light Irradiation

Catalysts ◽

10.3390/catal10020266 ◽

2020 ◽

Vol 10 (2) ◽

pp. 266 ◽

Cited By ~ 3

Author(s):

Xiujuan Yu ◽

Haiying Li ◽

Xueli Hao ◽

Zhiying Zhang ◽

Yan Wang ◽

...

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Benzyl Alcohol ◽

Selective Oxidation ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

Conversion Rate ◽

Light Irradiation ◽

X Ray ◽

Oxidation Of Benzyl Alcohol

A series of Ag/Pd/m-BiVO4 (monoclinic) bimetallic photocatalytic materials with different loading amounts and different mass ratios of Ag and Pd were synthesized by a hydrothermal method and an NaBH4 reduction method. The Ag/Pd/m-BiVO4 photocatalyst with a total Ag and Pd loading of 2 wt% and an Ag-to-Pd mass ratio of 2:1 can selectively oxidize benzyl alcohol to benzaldehyde under visible light irradiation, the conversion rate was up to 89.9%, and the selectivity was greater than 99%. The conversion rate on Ag/Pd/m-BiVO4 was higher than those on Ag/m-BiVO4 and Pd/m-BiVO4. The photocatalysts were characterized by X-ray powder diffraction (XRD), ultraviolet-visible diffuse reflection spectroscopy (UV-vis DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy, N2 adsorption-desorption isothermal curves (BET) and other means. The effects of different light wavelengths and light intensities were compared. Then, the effects of different alcohol derivatives on the reactions were explored. The cycle experiments proved that the Ag/Pd/m-BiVO4 photocatalyst had good light stability and thermal stability. In addition, the capturing experiment of active species shows that the selective oxidation of benzyl alcohol is mainly accomplished through the synergistic action of h+, e−, •OH and •O2−.

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Enhanced Photoactivity of Fe + N Codoped Anatase-RutileTiO2Nanowire Film under Visible Light Irradiation

International Journal of Photoenergy ◽

10.1155/2012/398508 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Kewei Li ◽

Haiying Wang ◽

Chunxu Pan ◽

Jianhong Wei ◽

Rui Xiong ◽

...

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

Synergistic Effects ◽

Anatase Phase ◽

Light Irradiation ◽

Codoped Sample ◽

X Ray ◽

Photocatalytic Activities

Rutile-anatase phase mixedFe+Ncodoped TiO2nanowires were designed and prepared by a two-step anodic oxidation method. The results of X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy confirm that the preparedFe+Ncodoped TiO2nanowires exhibit intimately contacted anatase-rutile heterostructure with the rutile content of 21.89%. The X-ray photoelectron spectroscopy measurements show that nitrogen and iron atoms are incorporated into the titania oxide lattice, and the UV-visible absorption spectra show that the codoping of iron and nitrogen atoms could extend the absorption to visible light region. The photocatalytic activities of all the samples were evaluated by photocatalytic degradation of methylene blue under visible light irradiation. TheFe+Ncodoped sample achieves the best response to visible light and the highest photocatalytic activities. The enhancement of photocatalytic activity forFe+Ncodoped sample should be ascribed to the synergistic effects of codoped nitrogen and iron ions and the anatase-rutile heterostructure.

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Synthesis of Nitrogen-Doped ZnS with Camellia Brushfield Yellow Nanostructures for Enhanced Photocatalytic Activity under Visible Light Irradiation

International Journal of Photoenergy ◽

10.1155/2013/801846 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Gang-Juan Lee ◽

Chi-Lun Hong ◽

Valentina Batalova ◽

Gennady Mokrousov ◽

Jerry Wu

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Visible Light ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

Light Irradiation ◽

X Ray ◽

Nitrogen Doped ◽

Composite Catalysts ◽

N Doping

Nitrogen modified zinc sulfide photocatalysts were successfully prepared and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), and surface area analysis. Thermal decomposition of the semisolid was carried out under nitrogen conditions at 500°C for 2 hours, and a series of nitrogen-doped ZnS photocatalysts were produced by controlling inflow flow rate of nitrogen at 15–140 mL/min. Optical characterizations of the synthesized N-doping ZnS substantially show the shifted photoabsorption properties from ultraviolet (UV) region to visible light. The band gaps of nitrogen-doped ZnS composite catalysts were calculated to be in the range of 2.58~2.74 eV from the absorptions edge position. The 15N/ZnS catalyst shows the highest photocatalytic activity, which results in 75.7% degradation of Orange II dye in 5 hrs by visible light irradiation, compared with pristine ZnS and higher percentage N-doping ZnS photocatalysts.

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Ag2O/ZnO Heterostructures with Enhanced Photocatalytic Activity

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1035.1043 ◽

2021 ◽

Vol 1035 ◽

pp. 1043-1049

Author(s):

Di Xiang ◽

Chang Long Shao

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Visible Light Irradiation ◽

Environmental Remediation ◽

Organic Dyes ◽

Light Irradiation ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

P Type

A simple route has been developed for the synthesis of Ag2O/ZnO heterostructures and the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS) and photoluminescence (PL) spectroscopy analysis. Considering the porous structure of Ag2O/ZnO, the photocatalytic degradation for the organic dyes, such as eosin red (ER), methyl orange (MO), methylene blue (MB) and rhodamine B (RhB), under visible light irradiation was investigated in detail. Noticeably, Ag2O/ZnO just took 40 min to degrade 96 % MB. The rate of degradation using the Ag2O/ZnO heterostructures was 2.3 times faster than that of the bare porous ZnO nanospheres under visible light irradiation due to that the recombination of the photogenerated charge was inhibited greatly in the p-type Ag2O and n-type ZnO semiconductor. So the Ag2O/ZnO heterostuctures showed the potential application on environmental remediation.

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Photocatalytic Decomposition of Methylene Blue with Lanthanum Doping TiO2 under Visible Light Irradiation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.734-737.2163 ◽

2013 ◽

Vol 734-737 ◽

pp. 2163-2167

Author(s):

Guang Xiu Cao ◽

Zhong Hou Zhang ◽

Bin Zhai

Keyword(s):

Methylene Blue ◽

Visible Light ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

Light Irradiation ◽

Photocatalytic Decomposition ◽

Lanthanum Doping ◽

X Ray ◽

Degradation Rates ◽

Vis Spectroscopy

Lanthanum doped TiO2 powders were prepared by hydrolysis of titanium tetra-n-butyl oxide and La (NO3)3 in solution. The resulting powders were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis absorption spectroscopy. The photocatalytic activities of doped samples were evaluated by the decomposition of methylene blue under visible light irradiation. The XRD results showed that the doping of lanthanum could not only efficiently inhibit the grain growth but also suppress the phase transition of anatase to rutile. UV-Vis spectroscopy of lanthanum doping TiO2 indicated that the absorption onset red-shifted to the visible light region. XPS results revealed that La2O3 had formed which could enhance the surface area. The degradation rates of methylene blue verified that the visible light photocatalytic activity of TiO2 has been enhanced by the doping of lanthanum.

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Noble metal-modified titania with visible-light activity for the decomposition of microorganisms

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.9.77 ◽

2018 ◽

Vol 9 ◽

pp. 829-841 ◽

Cited By ~ 11

Author(s):

Maya Endo ◽

Zhishun Wei ◽

Kunlei Wang ◽

Baris Karabiyik ◽

Kenta Yoshiiri ◽

...

Keyword(s):

Antibacterial Activity ◽

Visible Light ◽

Noble Metal ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Light Irradiation ◽

Localized Surface Plasmon ◽

Mycelium Growth ◽

X Ray

Commercial titania photocatalysts were modified with silver and gold by photodeposition, and characterized by diffuse reflectance spectroscopy (DRS), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning transmission electron microscopy (STEM). It was found that silver co-existed in zero valent (core) and oxidized (shell) forms, whereas gold was mainly zero valent. The obtained noble metal-modified samples were examined with regard to antibacterial (Escherichia coli(E. coli)) and antifungal (Aspergillus niger(A. niger),Aspergillus melleus(A. melleus),Penicillium chrysogenum(P. chrysogenum),Candida albicans(C. albicans)) activity under visible-light irradiation and in the dark using disk diffusion, suspension, colony growth (“poisoned food”) and sporulation methods. It was found that silver-modified titania, besides remarkably high antibacterial activity (inhibition of bacterial proliferation), could also decompose bacterial cells under visible-light irradiation, possibly due to an enhanced generation of reactive oxygen species and the intrinsic properties of silver. Gold-modified samples were almost inactive against bacteria in the dark, whereas significant bactericidal effect under visible-light irradiation suggested that the mechanism of bacteria inactivation was initiated by plasmonic excitation of titania by localized surface plasmon resonance of gold. The antifungal activity tests showed efficient suppression of mycelium growth by bare titania, and suppression of mycotoxin generation and sporulation by gold-modified titania. Although, the growth of fungi was hardly inhibited through disc diffusion (inhibition zones around discs), it indicates that gold does not penetrate into the media, and thus, a good stability of plasmonic photocatalysts has been confirmed. In summary, it was found that silver-modified titania showed superior antibacterial activity, whereas gold-modified samples were very active against fungi, suggesting that bimetallic photocatalysts containing both gold and silver should exhibit excellent antimicrobial properties.

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Synthesis, Characterization and Photocatalytic Performance of Novel Composite Ag/ BiVO4 Photocatalysts

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.79-82.2115 ◽

2009 ◽

Vol 79-82 ◽

pp. 2115-2118

Author(s):

Xian Hua Zhang ◽

Lei Ge

Keyword(s):

Visible Light ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

Light Irradiation ◽

The Novel ◽

X Ray Diffraction ◽

X Ray ◽

Composite Photocatalysts ◽

Visible Light Driven ◽

Composite Samples

The novel visible-light-driven Ag/BiVO4 composite photocatalysts were successfully prepared by photo-deposition method. The as-prepared Ag/BiVO4 samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and UV–vis diffuse reflectance spectra (DRS). The photocatalytic activities of the Ag/BiVO4 powders were determined by degradation of methyl orange molecules in water under visible light irradiation (λ>400nm). The photocatalytic experiments indicated that the composite samples enhanced photo-activity under visible light irradiation.

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