Search results for "Methyl orange"
showing 10 items of 19 documents
Mesocrystalline Cr and Sb-codoped anatase visible-light-driven photocatalyst
2018
Abstract We report on the synthesis, characterization and visible-light-driven photocatalytic activity of mesocrystalline Cr- and Sb-codoped anatase nanoparticles. Discrete and morphologically well-defined assemblies of anatase nanoparticles sized below 100 nm × 50 nm were prepared by hydrothermal aging of aqueous solutions containing titanium alkoxide, chromium acetylacetonate, antimony acetate and triethanolamine (TEOA) as stabilizer. The as-prepared and TEOA-free doped nanoparticles showed similar crystallographic parameters and spectroscopic features. The incorporation of Cr and Sb dopant cations into the anatase nanoparticles was evaluated by Rietveld refinement of X-ray diffraction pa…
Combined Adsorption/Photocatalytic dye removal by copper-titania-fly ash composite
2020
Abstract Achieving both photocatalytic efficiency and adsorption capacity is essential to produce a highly efficient photocatalyst. This study fabricated a new photocatalyst by combining copper (Cu) doped titanium dioxide (TiO2) with fly ash (FA). The photocatalysts were synthesized using mild acid (acid-FA/Cu/TiO2), base (base-FA/Cu/TiO2), and deionized water (rFA/Cu/TiO2) activated FA. EDX confirmed the inclusion of Cu in both Cu/TiO2 and FA/Cu/TiO2 composites. XRD analysis indicated the presence of the anatase form of TiO2 after Cu doping and incorporation into modified FA. All three FA/Cu/TiO2 composites demonstrated high absorption (UV and visible region) compared to their TiO2 and Cu/…
Characterization of methyl orange and its photocatalytic degradation products by HPLC/UV–VIS diode array and atmospheric pressure ionization quadrupo…
2002
Abstract HPLC/UV–VIS diode array and HPLC/MS techniques were successfully applied to the analysis of sulfonated molecules present in samples coming from the photocatalytic degradation of the azo dye indicator, methyl orange. The substrate was chosen as a simple model for the study of reactions involving the more complex commercial products used for the dyeing of textile fibers. Unexpected MS fragmentation path was observed, due to the very stable methyl orange molecular structure. The chromatographic information were combined with the obtained MS, MS/MS data and the UV–VIS diode array spectra and allowed to rationalize the molecular structures attributable to the various degradation product…
Azo-Dyes Photocatalytic Degradation in Aqueous Suspension of TiO2 Under Solar Irradiation
2002
Abstract The photodegradation of two common and very stable azo-dyes, i.e. methyl-orange (C14H14N3SO3Na) and orange II (C16H11N2SO4Na), is reported. The photocatalytic oxidation was carried out in aqueous suspensions of polycrystalline TiO2 irradiated by sunlight. Compound parabolic collectors, installed at the “Plataforma Solar de Almeria” (PSA, Spain) were used as the photoreactors and two identical reacting systems allowed to perform photoreactivity runs for the two dyes at the same time and under the same irradiation conditions. The disappearance of colour and substrates together with the abatement of total organic carbon content was monitored. The main sulfonate-containing intermediate…
A novel magnetic Preyssler acid grafted chitosan nano adsorbent: synthesis, characterization and adsorption activity
2015
BACKGROUND This study concerns the application of magnetic heteropolyacids composite for the adsorption of organic compounds from aqueous solutions. A novel magnetic Preyssler/chitosan/Fe3O4 nanoparticles composite (PCNF) adsorbent was designed using a one-pot synthesis method and characterized by multiple techniques including X-ray powder diffraction (XRD), infrared spectroscopy (FT-IR), N2 adsorption–desorption isotherms and scanning electron microscopy (SEM). RESULTS The adsorption activity of PCNF was evaluated by the removal of methyl orange (as an anionic azo dye model, MO) from aqueous solution and all the factors influencing the removal efficiency, such as adsorbent dosage, initial …
A comparative study of photocatalytically active nanocrystalline tetragonal T zyrcon- type and monoclinic scheelite-type bismuth vanadate
2018
The authors from Vinča Institute of Nuclear Sciences acknowledge the financial support of the Ministry of Education, Science and Technological Development of the Republic of Serbia (Project no: 172056 ). The work of K. Smits was supported by Latvian National Research Program IMIS2 (Grant no. 302/2012 ).
Enhancing the photocatalytic properties of PbS QD solids: the ligand exchange approach.
2019
Surface engineering of nanomaterials is a promising tool towards the design of new materials for conversion of solar energy into chemical energy. In this work, we examine the influence of ligand exchange on the photocatalytic performance of solution-processed PbS films. We test different ligands such as oleylamine (OAm), 1,2-ethanedithiol (EDT), 3-mercaptopropionic acid (MPA) and tetrabutylammonium iodide (TBAI). The study demonstrates that PbS films capped with MPA and EDT exhibit 3.5-fold enhanced photocatalytic performance for the photodecomposition of methyl orange upon sunlight exposure. Both band energy alignment and charge carrier transport have a strong impact on the generation of r…
Au–NiOx nanocomposite for hot electron-assisted plasmonic photocatalysis
2020
Nanocomposites of metal–oxide semiconductors containing Au nanoparticles are emerging multifunctional materials for sunlight-driven highly efficient photocatalysis. Here we report a solution-processed nanocomposite synthesis of Au–NiOx nanocomposite films by slot-die coating and plotter printing in a straightforward in situ synthesis approach. Our study demonstrated a significantly enhanced photocatalytic decomposition reaction of MO upon exposure of Au–NiOx films to a sunlight simulator. The excellent photocatalytic activity is ascribed to the generation of hot carriers after LSPR excitation in Au NPs. Suitable band alignment between the valence band of NiOx and the Fermi level of Au NPs l…
Customized WO3 nanoplatelets as visible-light photoelectrocatalyst for the degradation of a recalcitrant model organic compound (methyl orange)
2018
[EN] WO3 nanoplatelets have been synthesized by electrochemical anodization in acidic electrolytes containing two different complexing agents: fluorides and hydrogen peroxide. The influence of the morphology and size of these nanoplatelets on their photoelectrocatalytic performance has been studied following the degradation of a model organic recalcitrant compound, such as methyl orange (MO). The effect of several supporting electrolytes on this photodegradation process has also been checked. The best MO decoloration was observed for nanoplatelets fabricated in the presence of low H2O2 concentrations, whose distribution and small size made them expose a very high surface area to the problem…
Detection and correction of interferences in spectroscopy techniques
2001
By combining the apparent content curves method and the Youden method, we have developed a strategy for detecting constant and proportional errors in spectroscopy techniques. A method for elimination of spectral interferences (different of blank) is also proposed. To apply of this method there must be a matrix effect that varies with the amount of sample or a simulated matrix effect provided working under different experimental conditions that induce a variation of the analytical signal of the analyte. The proposed procedures have been applied to the determination of methyl orange in presence of phenol red, bromothymol blue and bromocresol purple.