scholarly journals Cyanamide-Modified Iron(III) Oxide Photocatalysts for Degradation of Phenol in the Presence of Urea and Formaldehyde

2021 ◽  
Vol 50 (12) ◽  
pp. 3569-3582
Author(s):  
Nur Azmina Roslan ◽  
Hendrik O. Lintang ◽  
Leny Yuliati Leny Yuliati
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Uv Light ◽  
Phenol Degradation ◽  
Fluorescence Emission ◽  
Light Irradiation ◽  
X Ray Diffraction ◽  
Carbon And Nitrogen ◽  
Fluorescence Emission Intensity ◽  
Xrd Patterns

Cyanamide as the source of carbon and nitrogen was used to modify iron(III) oxide (Fe2O3) photocatalyst. While X-ray diffraction (XRD) patterns confirmed that the cyanamide-modified Fe2O3 photocatalysts have comparable crystallinity to that of the unmodified Fe2O3, the diffuse reflectance ultraviolet-visible (DR UV-vis) spectra obviously showed additional light absorption around 500-800 nm on the cyanamide-modified Fe2O3, resulting in a better absorption capability under visible light irradiation. The presence of cyanamide modifier decreased the fluorescence emission intensity of Fe2O3, implying the reduced electron-hole recombination on the Fe2O3 and/or blocked emission sites by the modifier. The presence of carbon and nitrogen on the modified Fe2O3 photocatalysts was confirmed by the elemental analyzer. Photocatalytic activities of Fe2O3 and cyanamide-modified Fe2O3 were then evaluated for degradation of phenol under UV and visible light irradiation. Modification of Fe2O3 with cyanamide significantly improved the degradation of phenol from 30 to 75% under UV light irradiation and from 0 to 80% under visible light irradiation. Photocatalytic degradation of phenol was also investigated in the presence of urea or formaldehyde or both urea and formaldehyde. Even though the percentage of phenol degradation decreased in the presence of other pollutants, it was demonstrated that cyanamide modified iron(III) oxide photocatalysts still gave good activity towards degradation of phenol even in the presence of other organic pollutants.

Controllable Synthesis and Photocatalytic Activity of Ba0.6Mg0.4TiO3 Particles with Different Morphologies

2014 ◽  
Vol 955-959 ◽  
pp. 2267-2275 ◽  
Author(s):  
Rong Liu ◽  
Shi Duo Zhao ◽  
Xue Lin
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Hydrothermal Process ◽  
Light Irradiation ◽  
Photocatalytic Properties ◽  
X Ray Diffraction ◽  
Photocatalytic Activities ◽  
Uv Visible ◽  
Xrd Patterns

Ba0.6Mg0.4TiO3 (BMT) particles with different morphologies were synthesized through hydrothermal method and their optical and photocatalytic properties were investigated. Their crystal structure and microstructures were characterized using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). XRD patterns demonstrate that the as-prepared samples are tetragonal structure. FESEM shows that BMT crystals can be fabricated in different morphologies by simply manipulating the reaction parameters of hydrothermal process. The UV-visible diffuse reflectance spectra (UV-vis DRS) reveal that the band gaps of BMT photocatalysts are about 2.37 - 2.51 eV. The as-prepared BMT photocatalysts exhibite higher photocatalytic activities in the degradation of methyl orange (MO) under visible light irradiation (λ > 420 nm) compared with traditional N-doped TiO2 (N-TiO2) and pure BaTiO3 (BTO). The high photocatalytic performance of BMT photocatalysts could be attributed to the recombination restraint of the e-/h+ pairs resulting from doping of Mg2+ ions. The influence of morphologies upon the photocatalytic properties of BMT was studied. Furthermore, BMT nanowires reveal the highest photocatalytic activity. Up to 94.0% MO is decolorized after visible light irradiation for 360 min.

Photocatalytic Activity of CuO/ZnO Heterostructure Nanocrystals under UV-Visible Light Irradiation

2014 ◽  
Vol 787 ◽  
pp. 35-40 ◽  
Author(s):  
Xiao Yan Zhou ◽  
Peng Wei Zhou ◽  
Hao Guo ◽  
Bo Yang ◽  
Ru Fei Ren
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Cuo Nanoparticles ◽  
Light Irradiation ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Uv Visible

The p-n junction photocatalysts, p-CuO (at. 0-25%)/n-ZnO nanocomposite were prepared through hydrothermal method without using any organic solvent or surfactant. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-Ray spectroscopy, and UV-vis spectroscopy. The results demonstrated that the CuO/ZnO nanocomposite presented a two-dimensional morphology composed of sheet-like ZnO nanostructures adorned with CuO nanoparticles. The photocatalytic activity of CuO/ZnO with different Cu/Zn molar rations and pure ZnO synthesized by the identical synthetic route were evaluated by degrading methylene blue (MB) dye under UV-visible light irradiation. The CuO/ZnO with Cu/Zn molar ratio of 4% exhibits the highest photocatalytic activity compared that of the other photocatalysts under the identical conditions. It is mainly attributed to the increased charge separation rate in the nanocomposite and the extended photo-responding range.

Cyclopentadienyl ruthenium complexes with tricarbollide ligands

2010 ◽  
Vol 75 (11) ◽  
pp. 1139-1148 ◽  
Author(s):  
Dmitry S. Perekalin ◽  
Evgeniya A. Trifonova ◽  
Ivan V. Glukhov ◽  
Josef Holub ◽  
Alexander R. Kudinov
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Ruthenium Complexes ◽  
Light Irradiation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ca 50

Reaction of the tricarbollide anion [7,8,9-C3B8H11]– (1a) with the naphthalene complex [CpRu(C10H8)]+ under visible light irradiation in CH2Cl2 gives the 12-vertex closo-ruthenacarborane 1-Cp-1,2,3,5-RuC3B8H11 (2; 87% yield). This complex was also obtained by reaction of 1a with CpRu(cod)Cl (97%). Upon heating at 80 °C in toluene 2 rearranges into isomer 1-Cp-1,2,4,10-RuC3B8H11 (3; 63%). Irradiation of 1a with [CpRu(C10H8)]+ in acetone gives the 11-vertex closo-1-Cp-1,2,3,4-RuC3B7H10 (4; 32%). The latter was also prepared by reaction of 1a with [CpRu(MeCN)3]+ (59%). Compound 2 slowly undergoes cage contraction in acetone giving 4. Irradiation of 1a with [Cp*Ru(C10H8)]+ affords the isomeric 12-vertex closo-ruthenacarboranes 1-Cp*-1,2,3,5-RuC3B8H11 and 1-Cp*-1,2,4,10-RuC3B8H11 (2.2:1 ratio; 56%). Reaction of the amino-substituted tricarbollide anion [7-tBuNH-7,8,9-C3B8H10]– with [(C5R5)Ru(C10H8)]+ (R = H, Me) selectively gives 12-vertex closo-ruthenacarboranes 1-(C5R5)-12-tBuNH-1,2,4,12-RuC3B8H10 (ca. 50%). The structures of 2 and 4 were confirmed by X-ray diffraction.

Ag2O/ZnO Heterostructures with Enhanced Photocatalytic Activity

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.

A photo-auxiliary approach – enabling excited state classical phototransformations with metal free visible light irradiation

2017 ◽  
Vol 53 (10) ◽  
pp. 1692-1695 ◽  
Author(s):  
Akila Iyer ◽  
Steffen Jockusch ◽  
Jayaraman Sivaguru
Keyword(s):  
Excited State ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Uv Light ◽  
Light Irradiation ◽  
Metal Free ◽  
High Yields

To address the problem of using UV light to initiate traditional photoreactions, hydrazide based chromophores are evaluated as a “photo-auxiliary“ with visible light using a metal free photocatalyst to afford photoproducts in high yields.

scholarly journals Preparation and Characterizations of In0.1SnxZn0.85-2xS Powder Photocatalysts for Hydrogen Production under Visible Light Irradiation

2011 ◽  
Vol 364 ◽  
pp. 238-242 ◽  
Author(s):  
Kimi Melody ◽  
Yuliati Leny ◽  
Mustaffa Shamsuddin
Keyword(s):  
Hydrogen Production ◽  
Visible Light ◽  
Solid Solutions ◽  
Visible Light Irradiation ◽  
Diffuse Reflectance ◽  
Average Rate ◽  
Light Irradiation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Visible

A series of In0.1SnxZn0.85-2xS solid solutions was synthesized by hydrothermal method and employed as photocatalyst for photocatalytic hydrogen evolution under visible light irradiation. The structures, optical properties and morphologies of the solid solutions were studied by X-ray diffraction, diffuse reflectance UV–visible spectroscopy and field emission scanning electron microscopy. From the characterizations, it was confirmed that In0.1SnxZn0.85-2xS solid solution can be obtained and they have nanosized particles. The highest photocatalytic activity was observed on In0.1Sn0.03Zn0.79S photocatalyst, with average rate of hydrogen production 3.05 mmol/h, which was 1.2 times higher than the In0.1Zn0.85S photocatalyst.

A novel p-LaFeO3/n-Ag3PO4 heterojunction photocatalyst for phenol degradation under visible light irradiation

2016 ◽  
Vol 52 (12) ◽  
pp. 2620-2623 ◽  
Author(s):  
Jun Yang ◽  
Ruisheng Hu ◽  
Wanwan Meng ◽  
Yanfei Du
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Phenol Degradation ◽  
Light Irradiation

A novel p-LaFeO3/n-Ag3PO4 heterojunction photocatalyst exhibits higher activity than individual Ag3PO4 and LaFeO3 in the degradation of phenol.

Photocatalytic properties of p-n heterojunction Ag2CO3/Ag3PO4/Ni thin films under visible light

2019 ◽  
Vol 12 (06) ◽  
pp. 1950085 ◽  
Author(s):  
Di Zhao ◽  
Xuezheng An ◽  
Yaxian Sun ◽  
Guihua Li ◽  
Hongyan Liu ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Diffuse Reflectance ◽  
Diffuse Reflectance Spectroscopy ◽  
Light Irradiation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Photodegradation Efficiency

p-n heterojunction Ag2CO3/Ag3PO4/Ni thin films were prepared by electrochemical co-deposition. The surface morphology and structural properties of the thin films were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS). The photocatalytic (PC) properties of the Ag2CO3/Ag3PO4/Ni composite thin films were investigated by their ability to degrade rhodamine B (RhB) and Congo red (CR) under visible light irradiation. The results showed that the photodegradation efficiency of RhB by an Ag2CO3/Ag3PO4/Ni thin film under visible-light irradiation for 30[Formula: see text]min (98.84%) was 2.64 times higher than that of an Ag3PO4/Ni thin film and 3.44 times higher than of an Ag2CO3/Ni thin film. The presence of a [Formula: see text]-[Formula: see text] heterojunction greatly increased the charge conductivity of the film and its ability to photocatalytically reduce dissolved oxygen, which are the main reasons for the improved PC performance of the Ag2CO3/Ag3PO4/Ni films.

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