scholarly journals Diatom Biosilica Doped with Palladium(II) Chloride Nanoparticles as New Efficient Photocatalysts for Methyl Orange Degradation

2021 ◽  
Vol 22 (13) ◽  
pp. 6734
Author(s):  
Myroslav Sprynskyy ◽  
Paulina Szczyglewska ◽  
Izabela Wojtczak ◽  
Izabela Nowak ◽  
Andrzej Witkowski ◽  
...  
Keyword(s):  
Methyl Orange ◽  
Photocatalytic Degradation ◽  
Dye Degradation ◽  
Uv Light ◽  
Irradiation Time ◽  
Water Solution ◽  
Degradation Process ◽  
Solution Temperature ◽  
Scattering Effect ◽  
Light Excitation

A new catalyst based on biosilica doped with palladium(II) chloride nanoparticles was prepared and tested for efficient degradation of methyl orange (MO) in water solution under UV light excitation. The obtained photocatalyst was characterized by X-ray diffraction, TEM and N2 adsorption/desorption isotherms. The photocatalytic degradation process was studied as a function of pH of the solution, temperature, UV irradiation time, and MO initial concentration. The possibilities of recycling and durability of the prepared photocatalysts were also tested. Products of photocatalytic degradation were identified by liquid chromatography–mass spectrometry analyses. The photocatalyst exhibited excellent photodegradation activity toward MO degradation under UV light irradiation. Rapid photocatalytic degradation was found to take place within one minute with an efficiency of 85% reaching over 98% after 75 min. The proposed mechanism of photodegradation is based on the assumption that both HO• and O2•− radicals, as strongly oxidizing species that can participate in the dye degradation reaction, are generated by the attacks of photons emitted from diatom biosilica (photonic scattering effect) under the influence of UV light excitation. The degradation efficiency significantly increases as the intensity of photons emitted from biosilica is enhanced by palladium(II) chloride nanoparticles immobilized on biosilica (synergetic photonic scattering effect).

Magnetic field assisted photocatalytic degradation of organic dyes in the presence of Ag/TiO2 coated composite

2013 ◽  
Vol 67 (4) ◽  
pp. 722-728 ◽  
Author(s):  
Jian Wang ◽  
Jingqun Gao ◽  
Jun Wang ◽  
Yu Zhai ◽  
Zhongxing Wang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Rotational Speed ◽  
Organic Dyes ◽  
Dye Degradation ◽  
Uv Light ◽  
Irradiation Time ◽  
Sol Gel ◽  
Heat Treated

Ag/TiO2 coated composite was prepared via sol-gel method in order to elucidate its application in magnetic field assisted photocatalytic degradation of dyes. Through the degradation of organic dyes, the key influences such as Ag amount, heat-treated temperature and time on the photocatalytic activity of Ag/TiO2, as well as UV irradiation time, rotational speed, dye concentration and magnetic sheet number on the photocatalytic degradation were studied. Results showed that the Ag/TiO2 with 25 wt% Ag content heat-treated at 550 °C for 60 min has the best photocatalytic activity. With the increase of UV light irradiation time, rotational speed and magnetic sheet number, the degradation rate is improved. Different dye degradation proved that the method could universally be used.

Photocatalytic Degradation of Methyl Orange on Iron Niobate Prepared by Solid-State Reaction

2010 ◽  
Vol 113-116 ◽  
pp. 2021-2024 ◽  
Author(s):  
Wen Jie Zhang ◽  
Xin Sun ◽  
Bai Han Chen
Keyword(s):  
Methyl Orange ◽  
Solid State ◽  
Photocatalytic Degradation ◽  
Solid State Reaction ◽  
Irradiation Time ◽  
Molar Ratio ◽  
Preparation Conditions ◽  
New Type ◽  
Iron Niobate ◽  
Degradation Of Methyl Orange

Iron niobate photocatalyst as a new type of photocatalyst was prepared by solid-state reaction of Fe3O4 and Nb2O5 and its activity was evaluated using photocatalytic degradation of methyl orange. Preparation conditions such as calcination temperature and time, and irradiation time were investigated according to photocatalytic efficiencies. FeNb2O6 was produced during calcination below 700 oC and FeNbO4 was produced above 800 oC. Iron niobate with optimum activity could be prepared after calcination at 700 oC for 8 h when Fe:Nb molar ratio was 0.8:1. Methyl orange degradation rate was 72.7% after 180 min of irradiation at photocatalyst concentration of 4 g/l.

Electro-Assisted Photocatalytic Degradation of Methyl Orange on TiO2 Film Using CaСl2 as Electrolyte

2012 ◽  
Vol 487 ◽  
pp. 635-639
Author(s):  
Wen Jie Zhang ◽  
Hong Liang Xin ◽  
Hong Bo He
Keyword(s):  
Methyl Orange ◽  
Photocatalytic Degradation ◽  
Tio2 Film ◽  
Sol Gel ◽  
Degradation Process ◽  
Applied Potential ◽  
Methyl Orange Degradation ◽  
Degradation Rates ◽  
Smooth Film ◽  
Better Than

Porous and smooth TiO2 film electrodes prepared by sol-gel method were used on methyl orange degradation by an electro-assisted photocatalytic degradation process. Methyl orange cannot be degraded under applied potential solely below 2.0 V. When the applied potential was below 1.3 V, methyl orange degradation rates on porous TiO2 film increased from 5% at 0 V to 65.3% at 1.3 V, and degradation rates on smooth TiO2 film changed from 2.2% at 0 V to 61.1% at 1.3 V. Electro-assisted photocatalytic degradation rate on porous film was better than that on smooth film in the whole electrolyte concentration range. Electro-assisted degradation exhibited the same rising trend along with reaction time on the porous and smooth films.

scholarly journals Synthesis and characterization of CdS/UiO-66/Ag3PO4 nanocomposite for photocatalytic degradation of methyl orange under visible light irradiation

2021 ◽  
Vol 34 (3) ◽  
pp. 571-588
Author(s):  
T. Kebede ◽  
A. M. Taddesse ◽  
B. Ergedo
Keyword(s):  
Methyl Orange ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Visible Light Irradiation ◽  
Dye Degradation ◽  
Organic Pollutant ◽  
Light Irradiation ◽  
Sample Solution ◽  
Sewage Sample ◽  
Operational Parameters

Single, binary and ternary nanomaterials were synthesized by precipitation, solvothermal, simple solution and impregnation methods to serve as photocatalysts. The crystal structure, morphology, band gap energy, functional groups and optical properties of these materials were characterized by XRD, SEM-EDX, UV-Vis, FTIR, and PL instrumental techniques, respectively. Photocatalaytic degradation performances of all the as-synthesized photocatalysts were investigated under visible light irradiation using MO as a model organic pollutant. The photocatalytic degradation performances of all the photocatalysts were evaluated on aqueous solution of the model pollutant dye as well as on a real sewage sample solution collected from Bahir Dar Textile Share Company. Results suggested that the optimized ternary nanocomposite photocatalyst exhibited a relatively higher efficiency towards the photodegradation of both the methyl orange (MO) dye solution (90%) and the real sewage sample solution (71.2%). The effect of operational parameters such as pH (4), initial dye concentration (10 mg/L) and photocatalyst load (0.2 g/L) in MO dye degradation were investigated by using the ternary CdS/UiO-66/Ag3PO4 (R4) nanocomposite.                     KEY WORDS: Metal-organic frameworks, Nanocomposite, Ternary system, Photocatalysts, Methyl orange   Bull. Chem. Soc. Ethiop. 2020, 34(3), 571-588. DOI: https://dx.doi.org/10.4314/bcse.v34i3.12

scholarly journals Development of AgFeO2/rGO/TiO2 Ternary Composite Photocatalysts for Enhanced Photocatalytic Dye Decolorization

Crystals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 923
Author(s):  
Nasir Shehzad ◽  
Muhammad Zafar ◽  
Muhammad Ashfaq ◽  
Abdul Razzaq ◽  
Parveen Akhter ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Dye Degradation ◽  
Dye Decolorization ◽  
Degradation Process ◽  
Polluted Water ◽  
Ternary Composite ◽  
Composite Photocatalysts ◽  
Reduced Graphene ◽  
Vis Spectroscopy ◽  
Photocatalytic Dye Degradation

Dyestuff is one of the most widely released pollutants into the environment. Many approaches have been considered to deal with the dye removal from polluted water such as adsorption, ultrafiltration, osmosis, solvent extraction and photocatalytic degradation. The photocatalytic degradation process is one of the most beneficial, economical and environmentally friendly ways to degrade the organic pollutants from wastewater. In this study, an efficient ferrite-based photocatalyst, AgFeO2/rGO/TiO2 was successfully developed using simple deposition and reflux method. Physical, chemical and structural properties were analyzed by using XRD, FTIR Raman and PL spectroscopy. The efficiency of photocatalyst was investigated for the decolorization of methyl blue (MB) dye and activity was measured through UV-vis spectroscopy. The effect of parameters like pH, concentrations of MB dye, and loading of silver ferrite (AgFeO2) was investigated. The study depicted that the properties of TiO2 were improved due to addition of silver ferrite and reduced graphene oxide (rGO). The 2.5% AgFeO2/rGO/TiO2 exhibited the highest efficiency and completely degraded the 50 ppm of MB dye in 30 min. The parametric study revealed that dye decolorization is faster in a neutral solution than in basic and acidic medium. The higher performance of the photocatalyst was attributed to the reduced charge recombination and improved optical properties. Thus, AgFeO2/rGO/TiO2 can be a potential composite for photocatalytic dye degradation and other photocatalytic applications under UV-Visible light irradiations.

Preparation Conditions and Properties of Porous SiO2-Doped TiO2 Photocatalyst

2011 ◽  
Vol 214 ◽  
pp. 40-44
Author(s):  
Hong Li ◽  
Qian Li ◽  
Wen Jie Zhang
Keyword(s):  
Methyl Orange ◽  
Photocatalytic Degradation ◽  
Uv Light ◽  
Sol Gel ◽  
Doped Tio2 ◽  
Preparation Conditions ◽  
Uv Light Irradiation ◽  
Porous Sio2 ◽  
Increasing Temperature ◽  
Addition Amount

A porous SiO2-doped TiO2 photocatalyst was prepared through co-sol-gel method used for photocatalytic degradation of methyl orange. PEG1000 was used as a template. Photocatalytic degradation was conducted after adsorption equilibrium to identify the contribution of both adsorption and photocatalytic degradation. While PEG addition ranged from 0.25 g to 1.0 g, the optimum addition amount was at 0.5 g. The degradation rate increased with increasing calcination temperature in the range from 400 to 500 oC, and then it decreased with still increasing temperature. The photocatalyst calcinated at 500 oC for 4 h could degrade 29.2% of the initial methyl orange in 30 min. Nearly 96.5% of decoloration of the initial methyl orange was removed in 100 min under UV light irradiation with the existence of the porous SiO2-doped TiO2.

Electro-Assisted Photocatalytic Degradation of Methyl Orange on TiO2 Film Using NaCl as Electrolyte

2012 ◽  
Vol 457-458 ◽  
pp. 1169-1172
Author(s):  
Wen Jie Zhang ◽  
Mei Ling Hu ◽  
Hong Bo He
Keyword(s):  
Methyl Orange ◽  
Photocatalytic Degradation ◽  
Tio2 Film ◽  
Sol Gel ◽  
Porous Electrode ◽  
Degradation Process ◽  
Film Electrode ◽  
Degradation Rates ◽  
Smooth Film ◽  
Degradation Of Methyl Orange

Porous and smooth TiO2 film electrodes prepared by sol-gel method were used on methyl orange degradation by an electro-assisted photocatalytic degradation process. When using the applied potential along, there was no obvious degradation of methyl orange whether using TiO2 film electrode prepared using PEG template or not. The largest difference between the two electrodes appears at potential of 0.7 V in 0.05 mol/l NaCl solution, and the porous electrode shows better degradation activity in electro-assisted photocatalytic degradation. When NaCl concentration was 0.07 mol/l, degradation rates on porous and smooth film electrodes were 51.16% and 32.35 %, respectively. After 100 min of irradiation, 90% of the methyl orange degraded on the porous TiO2 film electrode, and 79.87% of the methyl orange degraded on the smooth TiO2 film electrode.

Sign in / Sign up

Export Citation Format

Share Document