Improved Photocatalytic Performance for Rhodamine B Degradation by Porous Zn2SnO4 Prepared with Carbon Black as a Pore-Forming Agent (original) (raw)
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Water, Air, & Soil Pollution, 2018
CoFe 2 O 4 /Zn 2 SnO 4 composite was synthesized using a simple two-step process and applied as a novel-efficient photocatalyst for the rhodamine B degradation from aqueous solution. Characterization techniques such as X-ray diffraction (XRD), N 2 adsorptiondesorption isotherms, scanning electron microscopy (SEM), EDS analysis, and diffuse reflectance spectroscopy were employed in order to investigate the physical and chemical properties of composite. Higher values of the specific surface area, pore volume and diameter, and a smaller band-gap energy promoted a greater catalytic activity of CoFe 2 O 4 /Zn 2 SnO 4 composite when compared to Zn 2 SnO 4. A rapid decolorization of dye solution was observed at 40 min of reaction using the CoFe 2 O 4 /Zn 2 SnO 4 catalyst, being 2.5 times faster than the Zn 2 SnO 4 alone. Therefore, the CoFe 2 O 4 /Zn 2 SnO 4 composite shows extraordinarily high photocatalytic activity toward the degradation of rhodamine B dye from aqueous solution. Keywords CoFe 2 O 4 /Zn 2 SnO 4. Synthesis. Coupled oxides. Photocatalysis. Rhodamine B
Photocatalytic degradation of rhodamine B dye using hydrothermally synthesized ZnO
Bulletin of Materials Science, 2006
The sunlight mediated photocatalytic degradation of rhodamine B (RB) dye was studied using hydrothermally prepared ZnO (T = 150°°C and P ~ 20-30 bars). Zinc chloride was used as the starting material along with sodium hydroxide as a solvent in the hydrothermal synthesis of ZnO. Different durations were tried to obtain pure ZnO phase, which was later confirmed through powder X-ray diffraction. The photocatalytic behaviour of the prepared ZnO was tested through the degradation of RB. The disappearance of organic molecules follows first-order kinetics. The effect of various parameters such as initial dye concentration, catalyst loading, pH of the medium, temperature of the dye solution, on the photo degradation of RB were investigated. The thermodynamic parameters of the photodegradation of RB, like energy of activation, enthalpy of activation, entropy of activation and free energy of activation revealed the efficiency of the process. An actual textile effluent containing RB as a major constituent along with other dyes and dyeing auxiliaries was treated using hydrothermally synthesized ZnO and the reduction in the chemical oxygen demand (COD) of the treated effluent revealed a complete destruction of the organic molecules along with colour removal.
2012
A combination of plasmonic nanoparticles (NPs) with semiconductor photocatalysts, called plasmonic photocatalysts, can be a good candidate for highly efficient photocatalysts using broadband solar light because it can greatly enhance overall photocatalytic efficiency by extending the working wavelength range of light from ultraviolet (UV) to visible. In particular, fixation of plasmonic photocatalysts on a floating porous substrate can have additional advantages for their recycling after water treatment. Here, we report on a floating porous plasmonic photocatalyst based on a polydimethylsiloxane (PDMS)−TiO 2 −gold (Au) composite sponge, in which TiO 2 and Au NPs are simultaneously immobilized on the surface of interconnected pores in the PDMS sponge. This can be easily fabricated by a simple sugar-template method with TiO 2 NPs and in situ reduction of Au NPs by the PDMS without extra chemicals. Its ability to decompose the organic pollutant rhodamine B in water was tested under UV and visible light, respectively. The results showed highly enhanced photocatalytic activity under both UV and visible light compared to the PDMS−TiO 2 sponge and the PDMS−Au sponge. Furthermore, its recyclability was also demonstrated for multiple cycles. The simplicity of fabrication and high photocatalytic performance of our PDMS−TiO 2 −Au sponge can be promising in environmental applications to treat water pollution.
Effective photocatalytic degradation of rhodamine B dye by ZnO nanoparticles
Materials Letters, 2013
Highly crystalline ZnO nanoparticles (NPs) were synthesized with zinc acetate as precursor and oxalic acid at 80 1C through the simple solution phase approach. The synthesized ZnO NPs possessed monodispersity with the average size 20-30 nm. The crystalline properties revealed the typical hexagonal wurtzite phase with orientation along c-axis. The photocatalytic activity investigation was carried out by performing the decomposition of rhodamine-B dye under UV illumination over assynthesized ZnO NPs. The rhodamine B dye considerably degraded by $ 95% within 70 min in the presence of as-synthesized ZnO NPs. An excellent rate constant (k¼ 0.0343 min À 1) was obtained for the degradation of rhodamine B dye.
Inorganic and Nano-Metal Chemistry, 2020
Undoped and B/Sn-doped ZnO nanoparticles are successfully produced by a simple mechanochemical method, and are characterized by XRD, FTIR, EDX, SEM, XPS and BET techniques. The XRD studies reveal that the prepared nanoparticles possess the hexagonal wurtzite structure of ZnO. The presence of various functional groups (-OH,-CH, Zn-O) are observed by FTIR. It is clear from EDX analysis that B, Sn, Zn and O elements are present in the nanoparticles. SEM images confirm the relatively smooth surface of B/Sn-doped ZnO nanoparticles. XPS results indicate that B and Sn are successfully doped into ZnO matrix. The photocatalytic performances of undoped and B/Sn-doped ZnO nanoparticles are investigated for the degradation of aqueous solution of Rhodamine B (RhB) dye in natural sunlight irradiation. The photocatalytic degradation of RhB dye in 1 h with B/Sn-doped ZnO nanoparticle is about 70.2%, which is significantly enhanced compared with the undoped ZnO (51.8%).
INTERNATIONAL SYMPOSIUM ON GREEN AND SUSTAINABLE TECHNOLOGY (ISGST2019)
Zinc oxide (ZnO) and titanium dioxide (TiO2) powders were hydrothermally modified in 10 M sodium hydroxide solutions at 120 °C for 24 hours to alter its morphologies. Hydrothermally treated ZnO and TiO2 showed partially rod-shaped particles and used as catalysts in the photocatalytic degradation of Rhodamine B under UV illumination. The effect of operational parameters on degradation efficiency such as catalyst loading (0.5 g/L to 2.5 g/L), initial dye concentration (2.5 ppm to 12.5 ppm), initial H2O2 concentration (0.1 M to 4.0 M) and solution pH (3 to 11) were studied. ZnO showed better photocatalytic activity as compared to TiO2 because ZnO has a lower bandgap energy and more active electron-hole pairs formation in the system. The optimum conditions were 0.5 M H2O2, 1.5 g/L ZnO suspension and 7.5 ppm Rhodamine B at neutral solution pH. The degradation of Rhodamine B followed pseudo first order reaction, with the apparent rate of reaction, kapp = 0.0501 min-1. An effective, efficient and environmental friendly method to remove organic dye from wastewater was developed and could be implemented in treating various types of organic pollutants.
International Journal of Molecular Sciences
Quasi-spherical undoped ZnO and Al-doped ZnO nanoparticles with different aluminum content, ranging from 0.5 to 5 at% of Al with respect to Zn, were synthesized. These nanoparticles were evaluated as photocatalysts in the photodegradation of the Rhodamine B (RhB) dye aqueous solution under UV-visible light irradiation. The undoped ZnO nanopowder annealed at 400 °C resulted in the highest degradation efficiency of ca. 81% after 4 h under green light irradiation (525 nm), in the presence of 5 mg of catalyst. The samples were characterized using ICP-OES, PXRD, TEM, FT-IR, 27Al-MAS NMR, UV-Vis and steady-state PL. The effect of Al-doping on the phase structure, shape and particle size was also investigated. Additional information arose from the annealed nanomaterials under dynamic N2 at different temperatures (400 and 550 °C). The position of aluminum in the ZnO lattice was identified by means of 27Al-MAS NMR. FT-IR gave further information about the type of tetrahedral sites occupied b...
The present study reports on the photo catalytic degradation of Rhodamine B, wet chemically synthesized ZnO photocatalyst. The average particle size and shape of synthesized ZnO were 24 nm and spherical, subsequently. The experiment was carried out by irradiating the aqueous solutions of dye containing photocatalysts with UV. The rate of decolourization was estimated from residual concentration spectrophotometrically. The experiment was carried out by varying the amount of catalyst (0.5, 1, 1.5 and 2 g/L) and initial concentration of dye (10–40 mg/L). The experimental results indicated that the maximum decolourization (more than 90%) of dyes occurred with ZnO catalyst at 1.5 g/L catalyst dose. The percentage reduction of Rhodamine B was estimated under UV system. Dye adsorption equilibrium was described by the Langmuir and Freundlich adsorption isotherms over the entire concentration ranging from 10 to 40 mg/L. Adsorption data are used for modelling, from the first- and second-order kinetic equation. The characteristic results and dimensionless factors showed that ZnO nanoparticles can be employed as commercial adsorbents in the removal of Rhodamine B from aqueous solution and wastewater. Keywords: Zinc nanoparticles; Adsorption isotherm; XRD; TEM; Rhodamine B
Tin as an Effective Doping Agent into ZnO for the Improved Photodegradation of Rhodamine B
Journal of Nanoscience and Nanotechnology
We have fabricated ZnO nano rods by hydrothermal method and successively doped them with tin (Sn) using different concentrations of 25, 50, 75 and 100 mg of tin chloride. XRD of the fabricated structures showed that ZnO possess hexagonal wurtzite phase. Scanning electron microscopy (SEM) was used to explore the morphology and it shows nanorod like morphology for all samples and no considerable change in the structural features were found. The dimension of nanorod is 200 to 300 nm. The doped materials were then investigated for their photo catalytic degradation of environmental pollutant Rhodamine B. The performance of doped ZnO is compared with the pristine ZnO. Scanning electron microscopy (SEM) was used to explore the morphology and it shows nanorod like morphology for all samples and no considerable change in the structural features were found. The dimension of nanorod is 200 to 300 nm. XRD of the fabricated structures showed that ZnO possess hexagonal wurtzite phase. Photo catal...