The Photocatalytic Degradation of Vehicle Exhausts by an Fe/N/Co–TiO2 Waterborne Coating under Visible Light

Based on the three-dimensional network structure of a polymer and the principle of photocatalysts, a visible-light-responsive and durable photocatalytic coating for the degradation of vehicle exhaust (VE) has been constructed using a waterborne acrylic acid emulsion as the coating substrate; Fe/N/Co–TiO2 nanoparticles (NPs) as photocatalytic components; and water, pigments, and fillers as additives. The visible-light-responsive Fe/N/Co–TiO2 NPs with an average size of 100 nm were prepared by sol-gel method firstly. The co-doping of three elements extended the absorption range of the modified TiO2 nanoparticles to the visible light region, and showed the highest light absorption intensity, which was confirmed by the ultraviolet-visible absorption spectra (UV-Vis). X-ray diffraction (XRD) measurements showed that element doping prevents the transition from anatase to rutile and increases the transition temperature. TiO2 was successfully doped due to the reduction of the chemical binding energy of Ti, as revealed by X-ray photoelectron spectroscopy (XPS). The degradation rates of NOX, CO, and CO2 in VE by Fe/N/Co–TiO2 NPs under visible light were 71.43%, 23.79%, and 21.09%, respectively. In contrast, under the same conditions, the degradation efficiencies of coating for VE decreased slightly. Moreover, the elementary properties of the coating, including pencil hardness, adhesive strength, water resistance, salt, and alkali resistance met the code requirement. The photocatalytic coating exhibited favorable reusability and durability, as shown by the reusability and exposure test.

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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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Band Gap Implications on Nano-TiO2 Surface Modification with Ascorbic Acid for Visible Light-Active Polypropylene Coated Photocatalyst

Nanomaterials ◽

10.3390/nano8080599 ◽

2018 ◽

Vol 8 (8) ◽

pp. 599 ◽

Cited By ~ 25

Author(s):

Chiara D’Amato ◽

Rita Giovannetti ◽

Marco Zannotti ◽

Elena Rommozzi ◽

Marco Minicucci ◽

...

Keyword(s):

Ascorbic Acid ◽

Surface Modification ◽

Visible Light ◽

Band Gap ◽

Tio2 Nanoparticles ◽

Photoelectron Spectroscopy ◽

Nano Tio2 ◽

Alizarin Red ◽

X Ray ◽

Visible Light Active

The effect of surface modification using ascorbic acid as a surface modifier of nano-TiO2 heterogeneous photocatalyst was studied. The preparation of supported photocatalyst was made by a specific paste containing ascorbic acid modified TiO2 nanoparticles used to cover Polypropylene as a support material. The obtained heterogeneous photocatalyst was thoroughly characterized (scanning electron microscope (SEM), RAMAN, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), and Diffuse Reflectance Spectra (DRS) and successfully applied in the visible light photodegradation of Alizarin Red S in water solutions. In particular, this new supported TiO2 photocatalyst showed a change in the adsorption mechanism of dye with respect to that of only TiO2 due to the surface properties. In addition, an improvement of photocatalytic performances in the visible light photodegration was obtained, showing a strict correlation between efficiency and energy band gap values, evidencing the favorable surface modification of TiO2 nanoparticles.

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Preparation of Visible-Light-Responsive TiO2-xNx Photocatalyst by a Very Simple Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.3188 ◽

2011 ◽

Vol 383-390 ◽

pp. 3188-3191

Author(s):

Han Jie Huang ◽

Wen Long She ◽

Ling Wen Yang ◽

Hai Peng Huang

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Photoelectron Spectroscopy ◽

Diffuse Reflection ◽

Ammonia Solution ◽

Reflection Spectra ◽

X Ray Diffraction ◽

Simple Method ◽

X Ray ◽

Light Excitation

A visible-light-responsive TiO2-xNx photocatalyst was prepared by a very simple method. Ammonia solution was used as nitrogen resource in this paper. The TiO2-xNx photocatalyst was characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), UV-Vis diffuse reflection spectra (DRS), and X-ray photoelectron spectroscopy (XPS). The ethylene was selected as a target pollutant under visible light excitation to evaluate the activity of this photocatalyst. The new prepared TiO2-xNx photocatalyst with strong photocatalytic activity under visible light irradiation was demonstrated in the experiment.

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FeYO3@rGO nanocomposites: Synthesis, characterization and application in photooxidative degradation of atrazine under visible light

Materials Express ◽

10.1166/mex.2021.1957 ◽

2021 ◽

Vol 11 (5) ◽

pp. 706-716

Author(s):

Nada D. Al-Khthami ◽

Tariq Altalhi ◽

Mohammed Alsawat ◽

Mohamed S. Amin ◽

Yousef G. Alghamdi ◽

...

Keyword(s):

Visible Light ◽

Photoelectron Spectroscopy ◽

Sol Gel ◽

Bandgap Energy ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Structural Surface ◽

Adsorption Desorption

Different organic pollutants have been remediated photo catalytically by applying perovskite photocatalysts. Atrazine (ATR) is a pesticide commonly detected as a pollutant in drinking, surface and ground water. Herein, FeYO3@rGO heterojunction was synthesized and applied for photooxidation decomposition of ATR. First, FeYO 3nanoparticles (NPs) were prepared via routine sol-gel. After that, FeYO3 NPs were successfully incorporated with different percentages (5, 10, 15 and 20 wt.%) of reduced graphene oxide (rGO) in the synthesis of novel FeYO3@rGO photocatalyst. Morphological, structural, surface, optoelectrical and optical characteristics of constructed materials were identified via X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Transmission electron microscopy (TEM), adsorption/desorption isotherms, diffusive reflectance (DR) spectra, and photoluminescence response (PL). Furthermore, photocatalytic achievement of the constructed materials was evaluated via photooxidative degradation of ATR. Various investigations affirmed the usefulness of rGO incorporation on the advancement of formed photocatalysts. Actually, novel nanocomposite containing rGO (15 wt.%) possessed diminished bandgap energy, as well as magnified visible light absorption. Furthermore, such nanocomposite presented exceptional photocatalytic achievement when exposed to visible light as ATR was perfectly photooxidized over finite amount (1.6 g · L-1) from the optimized photocatalyst when illuminated for 30 min. The advanced photocatalytic performance of constructed heterojunctions could be accredited mainly to depressed recombination amid induced charges. The constructed FeYO3@rGO nanocomposite is labelled as efficient photocatalyst for remediation of herbicides from aquatic environments.

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Synthesis of Hollow Flower-Like Fe3O4/MnO2/Mn3O4 Magnetically Separable Microspheres with Valence Heterostructure for Dye Degradation

Catalysts ◽

10.3390/catal9070589 ◽

2019 ◽

Vol 9 (7) ◽

pp. 589 ◽

Cited By ~ 4

Author(s):

Mingliang Ma ◽

Yuying Yang ◽

Yan Chen ◽

Fei Wu ◽

Wenting Li ◽

...

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Photoelectron Spectroscopy ◽

Organic Contaminants ◽

Dye Degradation ◽

Catalytic Performance ◽

X Ray ◽

Composite Microspheres ◽

Magnetically Separable ◽

Mno2 Nanosheet

In this manuscript, hollow flower-like ferric oxide/manganese dioxide/trimanganese tetraoxide (Fe3O4/MnO2/Mn3O4) magnetically separable microspheres were prepared by combining a simple hydrothermal method and reduction method. As the MnO2 nanoflower working as precursor was partially reduced, Mn3O4 nanoparticles were in situ grown from the MnO2 nanosheet. The composite microspheres were characterized in detail by employing scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), vibration sample magnetometer (VSM) and UV–visible spectrophotometer (UV–vis). Under visible light conditions, the test for degrading rhodamine B (RhB) was used to verify the photocatalytic activity of the photocatalyst. The results showed that the efficiency of the Fe3O4/MnO2/Mn3O4 photocatalyst in visible light for 130 min is 94.5%. The catalytic activity of photocatalyst far exceeded that of the Fe3O4/MnO2 component, and after four cycles, the catalytic performance of the catalyst remained at 78.4%. The superior properties of the photocatalyst came from improved surface area, enhanced light absorption, and efficient charge separation of the MnO2/Mn3O4 heterostructure. This study constructed a green and efficient valence heterostructure composite that created a promising photocatalyst for degrading organic contaminants in aqueous environments.

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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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Photocatalytic Performance of SiO2/CNOs/TiO2 to Accelerate the Degradation of Rhodamine B under Visible Light

Nanomaterials ◽

10.3390/nano9121671 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1671 ◽

Cited By ~ 2

Author(s):

Weike Zhang ◽

Yanrong Zhang ◽

Kai Yang ◽

Yanqing Yang ◽

Jia Jia ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Rhodamine B ◽

Photoelectron Spectroscopy ◽

Degradation Rate ◽

Photocatalytic Performance ◽

Sol Gel ◽

X Ray Diffraction ◽

X Ray ◽

Electronic Microscope

A silicon dioxide/carbon nano onions/titanium dioxide (SiO2/CNOs/TiO2) composite was synthesized by a simple sol-gel method and characterized by the methods of X-ray diffraction (XRD), scanning electronic microscope (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), Fourier transform infrared (FTIR), thermogravimetric analysis (TG), differential scanning calorimeter (DSC) and UV-Vis diffuse reflectance spectra (UV-Vis DRS). In this work, the photocatalytic activity of the SiO2/CNOs/TiO2 photocatalyst was assessed by testing the degradation rate of Rhodamine B (RhB) under visible light. The results indicated that the samples exhibited the best photocatalytic activity when the composite consisted of 3% CNOs and the optimum dosage of SiO2/CNOs/TiO2(3%) was 1.5 g/L as evidenced by the highest RhB degradation rate (96%). The SiO2/CNOs/TiO2 composite greatly improved the quantum efficiency of TiO2. This work provides a new option for the modification of subsequent nanocomposite oxide nanoparticles.

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Grafting Hyperbranched Polymers onto TiO2 Nanoparticles via Thiol-yne Click Chemistry and Its Effect on the Mechanical, Thermal and Surface Properties of Polyurethane Coating

Materials ◽

10.3390/ma12172817 ◽

2019 ◽

Vol 12 (17) ◽

pp. 2817 ◽

Cited By ~ 1

Author(s):

Feng Zhan ◽

Lei Xiong ◽

Fang Liu ◽

Chenying Li

Keyword(s):

Click Chemistry ◽

Tio2 Nanoparticles ◽

Photoelectron Spectroscopy ◽

Hyperbranched Polymers ◽

Nanocomposite Coatings ◽

Mechanical And Thermal Properties ◽

Nanoparticle Dispersion ◽

X Ray Diffraction ◽

X Ray ◽

Surface Modified

In this study, we proposed a novel and facile method to modify the surface of TiO2 nanoparticles and investigated the influence of the surface-modified TiO2 nanoparticles as an additive in a polyurethane (PU) coating. The hyperbranched polymers (HBP) were grafted on the surface of TiO2 nanoparticles via the thiol-yne click chemistry to reduce the aggregation of nanoparticles and increase the interaction between TiO2 and polymer matrices. The grafting of HBP on the TiO2 nanoparticles surface was investigated by means of X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), nuclear magnetic resonance (NMR) and thermogravimetry analysis (TGA). The thermal and mechanical properties of nanocomposite coatings containing various amounts of TiO2 nanoparticles were measured by dynamic mechanical thermal (DMTA) and tensile strength measurement. Moreover, the surface structure and properties of the newly prepared nanocomposite coatings were examined. The experimental results demonstrate that the incorporation of the surface-modified TiO2 nanoparticles can improve the mechanical and thermal properties of nanocomposite coatings. The results also reveal that the surface modification of TiO2 with the HBP chains improves the nanoparticle dispersion, and the coating surface shows a lotus leaf-like microstructure. Thus, the functional nanocomposite coatings exhibit superhydrophobic properties, good photocatalytic depollution performance, and high stripping resistance.

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Preparation of C, N and P co-doped TiO2 and its photocatalytic activity under visible light

Functional Materials Letters ◽

10.1142/s1793604719500450 ◽

2019 ◽

Vol 12 (04) ◽

pp. 1950045 ◽

Cited By ~ 3

Author(s):

Lin Zhao ◽

Yanzhao Xie ◽

Qiuyu Lin ◽

Rongze Zheng ◽

Yong Diao

Keyword(s):

Visible Light ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Sol Gel ◽

Soluble Starch ◽

Doping Amount ◽

X Ray ◽

Composite Catalysts ◽

One Step ◽

Co Doped

A series of composite catalysts of C, N and P co-doped TiO2 were prepared by sol-gel method, using a biomass (soluble starch) dopant. The samples were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (DRS), fourier transform infrared (FTIR) spectroscopy. The results show that TiO2 is co-doped with C, N and P by one step. The resulting composite exhibited higher specific surface area, wider visible-light absorption band with respect to the pure TiO2. The sample calcined at 400∘C for 2[Formula: see text]h with a doping amount of 6[Formula: see text]g soluble starch showed the best electrochemical performance. The C, N and P co-doped TiO2 was also used for the degradation of methylene blue (MB) and degradation ratio was up to 98% in 80[Formula: see text]min under visible light irradiation.

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Application of Reverse Micelle Sol–Gel Synthesis for Bulk Doping and Heteroatoms Surface Enrichment in Mo-Doped TiO2 Nanoparticles

Materials ◽

10.3390/ma12060937 ◽

2019 ◽

Vol 12 (6) ◽

pp. 937 ◽

Cited By ~ 5

Author(s):

Roberto Nasi ◽

Serena Esposito ◽

Francesca Freyria ◽

Marco Armandi ◽

Tanveer Gadhi ◽

...

Keyword(s):

Tio2 Nanoparticles ◽

Reverse Micelle ◽

Photoelectron Spectroscopy ◽

Sol Gel ◽

Actual State ◽

Test Reaction ◽

Potential Measurement ◽

X Ray ◽

Vis Spectroscopy ◽

Mo Content

TiO2 nanoparticles containing 0.0, 1.0, 5.0, and 10.0 wt.% Mo were prepared by a reverse micelle template assisted sol–gel method allowing the dispersion of Mo atoms in the TiO2 matrix. Their textural and surface properties were characterized by means of X-ray powder diffraction, micro-Raman spectroscopy, N2 adsorption/desorption isotherms at −196 °C, energy dispersive X-ray analysis coupled to field emission scanning electron microscopy, X-ray photoelectron spectroscopy, diffuse reflectance UV–Vis spectroscopy, and ζ-potential measurement. The photocatalytic degradation of Rhodamine B (under visible light and low irradiance) in water was used as a test reaction as well. The ensemble of the obtained experimental results was analyzed in order to discover the actual state of Mo in the final materials, showing the occurrence of both bulk doping and Mo surface species, with progressive segregation of MoOx species occurring only at a higher Mo content.

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