In this investigation, neodymium orthoferrite (NdFeO3) nanoparticles has been synthesized through ultrasonic method in the presence of octanoic acid as surfactant. This method comparing to the other methods is very fast and it does not need high temperatures during the reaction. The spherical NdFeO3 nanoparticles with an average particles size of about 40 nm can be obtained at a relatively high calcination temperature of 800 °C for 4 h. Also, product obtained by this method are uniform in both morphology and particles size. The phase composition, morphology, lattice parameters and size of particles in these product are characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDX). The XRD analysis reveals only the pattern corresponding to perovskite type NdFeO3 which crystallizes in the orthorhombic structure. Energy dispersive X-ray analysis confirms the elemental compositions of the synthesized material.
Pirochromite (MgCr2O4) nanoparticles were successfully prepared in this study. During synthesis of the pirochromite nanoparticles, a sol-gel was prepared by using magnesium acetate and potassium dichromate as magnesium and chromium sources and by using stearic acid as the network. Infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDX) were used for the elemental analysis, and diffuse reflectance spectroscopy (DRS) and vibrating sample magnetometer (VSM) were used in order to identify, provide a fuzzy diagnosis, and determine the size and morphology of the particles, as well as to analyze the optical and magnetic properties of the particles. The particle size of MgCr2O4 nanoparticles was observed to fall within a range of 39 nm–71 nm.
Copper oxide nanoparticles were successfully synthesized by mechanochemical reaction, which is a green, low cost, solvent free, rapid method and followed by calcining treatment. Copper acetate monohydrate and urea were used as reagents and the resulted precursor was calcined at 500 ?C for 2h in air. The scanning electron microscopy (SEM) revealed the formation of nanoparticles with an average size of about 86 nm. The Fourier transform infrared (FT–IR) spectrum and X-ray powder diffraction (XRD) pattern of the product confirmed all of reflections can be indexed to pure phase of CuO with a monoclinic crystal system. The diffuse reflectance spectrum (DRS) showed a band gap of 1.7 eV.
Tetraphenylporphyrin (TPP) and copper tetraphenylporphyrin (CuTPP) were synthesized and characterized by IR, UV-Vis, 1HNMR and 13CNMR. The CuTPP nanoparticles were synthesized by sonication and mixed solvent methods. These nanoparticles were characterized by AFM and SEM images and UV-Vis spectra. The catalytic activity of nanoparticles was investigated by oxidation of o-choloro and o-hydroxy benzyl alcohols in presence of molecular oxygen and isobutyraldehyde. The yields of oxidation of o-hydroxy benzyl alcohol by the two catalysts, CuTPP NPs and CuTPP, are 96.5% and ~ 2%, respectively. It is very obvious that the oxidation at the presence of CuTPP NPs catalyst is very high but selectivity for both reactants is 100%.?