Impact of dysprosium doped (Dy) zinc ferrite (ZnFe2o4) nanocrystals in photo- fenton exclusion of recalcitrant organic pollutant.

The issue of effluent, especially organic colorants from several manufacturing units overlays an immense delinquent of the current epoch owing to its effect on oncogenic health hazards. Thus, Rare Earth Metal dysprosium (Dy) doped Zinc Ferrite (ZnFe2O4) were as-synthesized by a facile co-precipitation technique as an effectual nano photocatalyst intended to the amputation of these noxious dyes. The structural, functional, optical, magnetic, and degradation properties of this RE (Dy3+) doped ions were investigated using various characterizations, such as crystallite size (D) and several parameters (cation distribution, oxygen positional parameters, and bond length) were determined using XRD (X-ray diffraction) and it was found that as the dy3+ ion concentration increases the speck size decreased and the grain size remained within nano regime, which intern affects the surface area. From BET analysis it was found that on increasing the doping concentration, the surface area increases which pave a substantial role in the photo-Fenton activity. By using FT-IR (Fourier-transform infrared spectroscopy) various functional parameters (elastic, interionic bonds, ion distribution, etc.) were determined. Raman spectra had no extra peak formation which is seen to have pure phase formation of the as-synthesized samples. HR-TEM (High-Resolution Transmission Electron Microscopy analysis were done to determine the nature of the sample, the as-synthesized magnetic samples exhibit a polycrystalline formation with cubical agglomeration. The magnetic property was very significant for x = 0.10 concentration. As-synthesized (Fe0.9064Zn0.0936) [Fe1.0936Dy0.1Zn0.8064] O4) exhibits a momentous photo - Fenton activity against MB (Methylene blue), its removal efficiency was found to be 97.3% after 45 min. Also, this spinel ferrite acts as a magnetic recyclable catalyst even after 5 cycles with an insignificant lessening of elements and photo-Fenton activity.

Exploring the influence of varying pH on structural, electro-optical, magnetic and photo-Fenton properties of mesoporous ZnFe2O4 nanocrystals.

An economically viable and superficial technique was indorsed to yield ZnFe2O4 nanocrystals in the system to investigate the impact of pH variation on the optical, structural, electrical, and magnetic properties of as-prepared nanocrystals. The as-synthesized ZnFe2O4 nanocrystals were premeditated with the application protracted to degradation of Methylene blue organic dye. The results specify that the pH plays the utmost decisive facet in photo-Fenton recital. From XRD (X-Ray diffraction) analyses, it was confirmed that as-synthesized nanocrystals belong to a cubic Fd3m crystal phase. The crystallite size was also determined by the Scherrer formula and it was noticed that as the pH rises the crystallite size also increased. FT-IR (Fourier Transform Infrared) analysis depicts two absorption peaks âˆ¼ 500 and ∼600 cm-1 that represents tetrahedral (Td) and octahedral (Oh) sites. Using TEM (Transmission Electron Microscopy), the morphology was observed to be spherical particles with some agglomeration. Photoluminescence and UV-visible spectral studies were performed to investigate the optical properties. The bandgap energy was seen to decrease as the pH increased. Using BET analysis, the surface area for the as-synthesized samples was found to decrease on increasing the pH. The reaction results showed that the ZnFe2O4 has good photocatalytic activity, which can be attributed to high surface area and pore volume, and large pore size. The ZnFe2O4 produced by the co-precipitation route exhibited promising photocatalytic activity for the removal of textile dye, reaching nearly 99.2% of decolorization at 100 min. Therefore, ZnFe2O4 particles rapidly prepared by the co-precipitation route have the potential for use in treatment of textile wastewater by the heterogeneous photo-Fenton process. With the help of VSM analysis, the coercivity and other magnetic properties were determined for the as-synthesized nanocrystal with plays a significant role in photocatalytic recyclability, which intends to premediate that the prepared nanocrystals can be used in industrial persistence.

Effect of Lanthanum Substitution on Magnetic and Structural Properties of Nickel Ferrite.

Inverse spinel ferrites have demanded substantial attention in the recent past owing to their diverse technological deeds by conquering admirably with its surface, finite size effects and optical properties which has its proficient applications in photocatalytic degradation, magnetic resonance imaging and sensors etc. The substituted La3+ ions delay the development of grain growth of the materials in a meticulous manner compared with that of the pure Ni ferrites. We tale development of magnetic features in La3+ substituted Ni nano-ferrites synthesized by co-precipitation technique and then analyzed from the structural and magnetic perspectives. A credible and thriftily doable co-precipitation method has been the spotlight of forethought in recent decades to synthesize these ferrite nanoparticles. Enviable inverse spinel phase has been observed, as it is essential to modify and optimise its micro structural and magnetic features. The phase formation and significant properties of Ni1-xLaxFe2O4 ferrites were investigated using XRD, FTIR, TEM, UV-visible, VSM and FT-Raman techniques. The crystallite size of the as-synthesized nanoparticles were observed after the substitution of La3+ content in the range of 8 to 15 nm. As the dopant concentration increases the crytallite size increases and other changes in crystallographic parameters, as well as the cation distribution also observed. The TEM micrograph clearly reveals the cubic and the notable polycrystalline nature. The FTIR measurements carried out in the range of 400-4000 cm-1 elucidates the occurrence of functional groups. The UV-visible spectrum analysis reveals the optical property of as-synthesized nanoparticle and hence their band gap was found using Kubelka-Munk plot. The magnetic parameters were studied by vibrating sample magnetometer and the saturation magnetization of the ferrites at the room temperature decreases with the reduction in size.

Investigation on the Magnetically Separable Zn Substituted CoFe2O4 Nanoparticles with Enhanced Photo-Fenton Degradation.

We report the influence of Co1-xZnxFe2O4 nanoferrites for the photodegradation of organic pollutant present in the aqueous solution. A series of Co1-xZnxFe2O4 (x = 0.01, 0.03, 0.05 and 0.10) nanoferrites have been synthesized via a facile and economically viable coprecipitation technique and investigated the effect of zinc dopant in their structural, optical, electrical and magnetic properties. X-ray diffraction and Fourier Transform Infrared spectral studies reveal the spinel phase formation of the as-synthesized nanoferrites. Photoluminescence and UV-visible spectral studies show the bandgap of nanoferrites increase from 2.47-2.67 eV and exhibited a blue shift in the band edge emission with respect to increase in Zn content. Phase transition of the samples from weak ferromagnetic to superparamagnetic nature has been observed by Vibrating Sample Magnetometer at room temperature. Furthermore, the Co1-xZnxFe2O4 was assessed for the degradation of Methylene Blue (MB) dye and the sample with Co1-0.10Zn0.10Fe2O4 showed better photocatalytic degradability of organic MB due to its enhanced adsorption in the visible region and the existence of lower concentration charge-carriers.