One-Pot Fabrication of K-Doped g-C3N4/SiO2Composite with Enhanced Photocatalytic Activity for Degradation of Tetracycline

K-doped g-C3N4/SiO2composite (SiO2/K-CN) was synthesized by a facile thermal polymerization with potassium chloride, melamine and nano-silica as raw materials. The as-prepared SiO2/K-CN was characterized by various measures. The photocatalytic activity of SiO2/K-CN was tested via the photocatalytic degradation of tetracycline under visible-light irradiation. The results showed that the specific surface area of SiO2/K-CN catalyst was 28.16m2/g, which is larger than that of pristine K-doped g-C3N4. Both K-doping and silica-combination can reduce the recombination rate of photo-generated electrons-holes pairs and broaden the region of visible light-harvesting. Compared with the pristine K-doped g-C3N4 and composite SiO2/g-C3N4, SiO2/K-CN exhibits distinctly higher photocatalytic activity for degradation of tetracycline. The enhanced photocatalytic performance of SiO2/K-CN is attributed to the increased specific surface area and the synergistic effect of K-doping and silica-combination in both accelerating separation of charged carries and improving visible light-absorption. During photocatalytic degradation of tetracycline, superoxide radicals play the most important role, followed by holes.SiO2/K-CN complex has excellent stability and shows promising application in photocatalytic degradation of organic contaminants in water.

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One-step synthesis of spherical NaTaO3 and graphene spherical NaTaO3 nanoparticles with enhanced photocatalytic activity for NO purification

Functional Materials Letters ◽

10.1142/s1793604718500704 ◽

2018 ◽

Vol 11 (04) ◽

pp. 1850070 ◽

Cited By ~ 2

Author(s):

Zimao Ding ◽

Sheng Guo ◽

Xiaoyong Wu ◽

Hussain Fida

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Uv Irradiation ◽

Mixed Solution ◽

One Pot ◽

Photocatalytic Ability ◽

Water Glycerol

To obtain efficient photocatalytic air purification, a series of NaTaO3 nanoparticles were successfully synthesized through a one-pot solvothermal approach, using water/glycerol mixed solution as solvent. The glycerol not only played an important role for controlling the morphology and particle size, but also remarkably enhanced the specific surface area of the as-prepared NaTaO3. Under optimal conditions, the spherical NaTaO3 (NaTaO3-30) exhibited much higher deNO[Formula: see text] performance under UV irradiation as compared to the cubic NaTaO3 (NaTaO3-0). Furthermore, the graphene spherical NaTaO3 composites were also prepared to further enhance the visible light driven photocatalytic ability of spherical NaTaO3. When 1[Formula: see text]wt.% graphene was loaded, the spherical NaTaO3/graphene showed excellent performance for continuous NO gas destruction under UV irradiation, short wavelength visible light ([Formula: see text][Formula: see text]nm) and even long wavelength visible light ([Formula: see text][Formula: see text]nm), which was superior to spherical NaTaO3 and cubic NaTaO3/graphene. The increased specific surface area, expanded light absorption and accelerated electron transport were responsible for the enhanced photocatalytic activity of the composite. The present work may shed new light on the synthesis of novel perovskite-type NaTaO3-based catalysts with excellent photocatalytic performance.

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Enhanced photocatalytic activity of a hollow TiO2–Au–TiO2 sandwich structured nanocomposite

RSC Advances ◽

10.1039/c5ra26646g ◽

2016 ◽

Vol 6 (23) ◽

pp. 18958-18964 ◽

Cited By ~ 10

Author(s):

Qianqian Ding ◽

Yunxia Zhang ◽

Guozhong Wang ◽

Hongjian Zhou ◽

Haimin Zhang

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Large Specific Surface Area

The hollow mesoporous TiO2–Au–TiO2 nanospheres with stability, large specific surface area can enhance visible-light-induced photocatalytic activity.

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Photocatalytic degradation of metoxuron in aqueous suspensions ofTiO2. Analytical and kinetic studies

International Journal of Photoenergy ◽

10.1155/s1110662x0200017x ◽

2002 ◽

Vol 4 (4) ◽

pp. 147-151 ◽

Cited By ~ 7

Author(s):

Amina Amine Khodja ◽

Bernadette Lavedrine ◽

Claire Richard ◽

Tahar Sehili

Keyword(s):

Photocatalytic Activity ◽

Specific Surface ◽

Photocatalytic Degradation ◽

Surface Area ◽

Specific Surface Area ◽

Kinetic Studies ◽

Photocatalytic Efficiency ◽

Aqueous Suspensions ◽

Degussa P25 ◽

Ring Hydroxylation

The photocatalytic degradation of metoxuron [3-(3-chloro-4-methoxyphenyl)-1,1-dimethylurea] in aqueous suspensions ofTiO2was investigated. Several intermediate photoproducts were identified using NMR and MS techniques. Oxidation or removal of the methyl of terminal nitrogen and ring hydroxylation were found to occur. 2-Propanol was shown to decrease the rate of photocatalytic degradation, inhibiting partly ring hydroxylation and completely reactions on terminal nitrogen. In contrast, basification of the suspensions accelerated the degradation significantly. Degussa P25TiO2was found to exhibit a higher photocatalytic activity than MillenniumTiO2in spite of a generally smaller specific surface area. Within the MillenniumTiO2series, the photocatalytic efficiency increased with the specific surface area.

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TiO2 composite films on different substrates with enhanced visible light photocatalytic performance

Functional Materials Letters ◽

10.1142/s1793604720510376 ◽

2020 ◽

Vol 13 (07) ◽

pp. 2051037

Author(s):

Ke Han ◽

Guobao Li ◽

Fang Li ◽

Mingming Yao

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Photocatalytic Performance ◽

Sol Gel ◽

Composite Films ◽

Methyl Green ◽

Photogenerated Electrons

For the sake of improving the photocatalytic performance of TiO2, we prepared the B/Ag/Fe tridoped TiO2 films on common glass and stone substrates by the sol–gel method. In this work, the optical absorption, recombination of photogenerated electrons (e−) and holes (h[Formula: see text]), crystal types, thermal stability, composition, specific surface area and photocatalytic activity of the modified TiO2 films were investigated. The results indicated that B/Ag/Fe tridoping not only enhanced the absorption of visible light by TiO2, but inhibited the recombination of electron–hole (e−/h[Formula: see text]) pairs. The tridoping also promoted the formation of anatase and prevented the transformation of anatase to rutile at high temperature. The composite TiO2 has a large specific surface area, about three times that of pure TiO2. The photocatalytic activity of the TiO2 films were evaluated by methyl green (MG) and formaldehyde degradation. In all samples, the B/Ag/Fe tridoped TiO2 film exhibited the highest degradation rate of MG under both ultraviolet and visible light irradiation. The improvement of photocatalytic performance of TiO2 films is due to the synergistic effect of the B/Ag/Fe tridoping, which enhances the absorption of visible light and prolongs the lifetime of e−/h[Formula: see text] pairs and facilitates transfer of interface charge.

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Visible light responsive mesoporous graphene–Eu2O3/TiO2 nanocomposites for the efficient photocatalytic degradation of 4-chlorophenol

RSC Advances ◽

10.1039/c5ra27541e ◽

2016 ◽

Vol 6 (41) ◽

pp. 35024-35035 ◽

Cited By ~ 29

Author(s):

Mallanaicker Myilsamy ◽

Mani Mahalakshmi ◽

Nallasivam Subha ◽

Ariyamuthu Rajabhuvaneswari ◽

Velayutham Murugesan

Keyword(s):

Charge Transfer ◽

Visible Light ◽

Specific Surface ◽

Photocatalytic Degradation ◽

Surface Area ◽

Specific Surface Area ◽

Red Shift ◽

Transfer Efficiency ◽

Co Doped

Graphene and europium co-doped on TiO2 nanocomposites synergistically enhanced the photocatalytic degradation of 4-chlorophenol under visible light due to the enhanced specific surface area with red shift and improved charge transfer efficiency.

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Three-Dimensional Zn0.5Cd0.5S/Reduced Graphene Oxide Hybrid Aerogel: Facile Synthesis and the Visible-Light-Driven Photocatalytic Property for Reduction of Cr(VI) in Water

Journal of Nanomaterials ◽

10.1155/2016/6201546 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 6

Author(s):

Wei Xiao ◽

Wenjie Zhou ◽

Yanhua Zhang ◽

Liangliang Tian ◽

Hongdong Liu ◽

...

Keyword(s):

Photocatalytic Activity ◽

Graphene Oxide ◽

Visible Light ◽

Specific Surface ◽

Reduced Graphene Oxide ◽

Surface Area ◽

Specific Surface Area ◽

Three Dimensional ◽

Reduced Graphene ◽

Visible Light Driven

A series of three-dimensional ZnxCd1-xS/reduced graphene oxide (ZnxCd1-xS/RGO) hybrid aerogels was successfully synthesized based on a one-pot hydrothermal approach, which were subsequently used as visible-light-driven photocatalysts for photoreduction of Cr(VI) in water. Over 95% of Cr(VI) was photoreduced by Zn0.5Cd0.5S/RGO aerogel material within 140 min, and such photocatalytic performance was superior to that of other ZnxCd1-xS/RGO aerogel materials (x≠0.5) and bare Zn0.5Cd0.5S. It was assumed that the enhanced photocatalytic activity of Zn0.5Cd0.5S/RGO aerogel was attributed to its high specific surface area and the preferable synergetic catalytic effect between Zn0.5Cd0.5S and RGO. Besides, Zn0.5Cd0.5S/RGO aerogel materials were robust and durable enough so that they could be reused several times with merely limited loss of photocatalytic activity. The chemical composition, phase, structure, and morphology of Zn0.5Cd0.5S/RGO aerogel material were carefully examined by a number of techniques like XRD, SEM, TEM, BET, Raman characterizations, and so on. It was found that Zn0.5Cd0.5S/RGO aerogel possessed hierarchically porous architecture with the specific surface area as high as 260.8 m2 g−1. The Zn0.5Cd0.5S component incorporated in Zn0.5Cd0.5S/RGO aerogel existed in the form of solid solution nanoparticles, which were uniformly distributed in the RGO matrix.

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Development of a novel photocatalyst for the photocatalytic treatment of industrial wastewater

10.32920/ryerson.14647518.v1 ◽

2021 ◽

Author(s):

Mohsen Nasirian

Keyword(s):

Photocatalytic Activity ◽

Transition Metal ◽

Visible Light ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Mass Ratio ◽

Thermal Synthesis ◽

Composite Photocatalyst ◽

X Ray

Heterogeneous semiconductor photocatalysts have been shown to be efficient for the degradation of refractory organics into simple compounds. Among all photocatalysts, TiO2 is the most used one. Two issues that arise with the use of unmodified TiO2 as a photocatalyst are the unwanted fast recombination of electron/hole pairs and the lower effectiveness in the presence of visible light irradiation. Doping a transition metal or a non-metal into TiO2 and its combination with another photocatalyst have been used to enhance its photoactivity. This study is to develop a new photocatalyst by the combination of TiO2 with another semiconductor oxide (Fe2O3) and its doping with transition metal such as Ag. Combined photocatalysts of Fe2O3 /TiO2 (with different mass ratio of Fe:TiO2) is synthesized and then silver ion is doped to combine photocatalysts (with different mass ratio of Ag:TiO2) to produce a new composite photocatalyst of Ag/TiO2/Fe2O3. A new method of UV-assisted thermal synthesis is also employed to prepare the new composite photocatalyst. Methyl orange (MO) and Congo red (CR), as model pollutants, are used to test the developed photocatalyst. In addition, nitrogen-doped titanium dioxide photocatalyst (N-TiO2) with heterojunction structures is synthesized by three different approaches including new UV-assisted thermal synthesis, annealing, and microwave techniques. The novel UV-assisted thermal synthesis has produced encouraging results as a preparation method to prepare N-TiO2 at lower temperature and atmospheric pressure as well as a lower cost. Design of Experiment (DOE) along with response surface methodology (RSM) is used to optimize the photocatalytic activity of N-TiO2 as well as the affecting parameters (wavelength, light intensity, pH, and initial TOC) for decomposition of organics. The structure of all synthesized composite photocatalysts are investigated by X-ray diffraction (XRD). Scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDS) is employed to evaluate surface characteristics and elemental analysis of synthesized photocatalysts. Specific surface area of photocatalysts is measured based on Brunauer, Emmett and Teller (BET) technique. Results show that bare TiO2 has the lowest photocatalytic activity in degradation of organics. When silver is doped to TiO2, the degradation of MO is slightly enhanced at specific mass ratio. The presence of Fe2O3 in the new composite causes a red shift and enhances the potential to absorb higher range of visible light. Results from XRD confirmed that Fe3+ substitutes with Ti4+ in the crystal lattice of TiO2 and crystal defect occurs. The degradation of MO in presence of Ag/TiO2/Fe2O3 (Ag/TiO2=0.005 w:w and Fe:TiO2= 0.01 w:w) reached to 95.6% under sunlight in three hours with a red shift towards visible light. It is observed that there is an optimum specific surface area of photocatalysts by doping and combining photocatalysts.

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Facile one-pot synthesis of MoS2 quantum dots–graphene–TiO2 composites for highly enhanced photocatalytic properties

Chemical Communications ◽

10.1039/c4cc08984g ◽

2015 ◽

Vol 51 (9) ◽

pp. 1709-1712 ◽

Cited By ~ 117

Author(s):

Weiyin Gao ◽

Minqiang Wang ◽

Chenxin Ran ◽

Le Li

Keyword(s):

Quantum Dots ◽

Visible Light ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Charge Separation ◽

One Pot ◽

Composite Photocatalyst ◽

One Pot Synthesis ◽

Light Absorbance

We reported a simple one-pot solvothermal approach to fabricate MoS2 quantum dots (QDs)–graphene–TiO2 (MGT) composite photocatalyst with significant improved photocatalysis property, which is caused by the increased charge separation, visible-light absorbance, specific surface area and reaction sites upon the introduction of MoS2 QDs.

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The Simplest Way to Iodine-Doped Anatase for Photocatalysts Activated by Visible Light

International Journal of Photoenergy ◽

10.1155/2011/685935 ◽

2011 ◽

Vol 2011 ◽

pp. 1-13 ◽

Cited By ~ 18

Author(s):

Václav Štengl ◽

Tomáš Matys Grygar

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Aqueous Suspension ◽

Organometallic Compounds ◽

Orange Ii ◽

Iodine Doping ◽

Doped Titania

Iodine-doped TiO2was prepared by thermal hydrolysis of aqueous solutions of the titanium peroxo-complex, which includes no organic solvents or organometallic compounds. The synthesized samples were characterized by X-ray diffraction (XRD), Raman spectroscopy (RS), infrared spectroscopy (IR), specific surface area (BET), and porosity determination (BJH). The morphology and particle size was determined by high-resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED). All prepared samples have a red-shifted band-gap transition, well crystalline anatase structure, and porous particles with a 100–200 m2 g−1specific surface area. The photocatalytic activity of iodine-doped titania samples was determined by decomposition of Orange II dye during irradiation at 365 nm and 400 nm. Iodine doping promotes the titania photocatalytic activity very efficiently under visible light irradiation. The titania sample with 0.32 wt.% I has the highest catalytic activity during the photocatalyzed degradation of Orange II dye in an aqueous suspension in the UV and visible regions.

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