Microwave-assisted synthesis of CePO<Subscript>4</Subscript> nanorod phosphor with violet emission

Monoclinic and hexagonal CePO4 nanoparticles and nanorods were successfully synthesized from Ce(NO3) 3·6H2O and Na3PO4·12H2O solu-tions at pH 1-5 by a 180 W microwave radiation for 60 min.The products were characterized by X-ray diffraction(XRD) ,Fourier transform infrared(FTIR) spectroscopy,and scanning electron microscopy(SEM) .XRD patterns revealed that the products are hexagonal CePO4 structures at pH 2-5,and monoclinic CePO4 structures at pH 1.SEM characterization shows that these products were nanoparticles,short nanorods,and long nanorods,controlled by the pH of the precursor solutions.Optical properties of the nanorods were also investigated by ultraviolet-visible(UV-vis) and photoluminescence(PL) spectroscopy.     

Glycolthermal synthesis and characterization of hexagonal CdS round microparticles in flower-like clusters

Hexagonal CdS round microparticles in flower-like clusters were synthesized by glycolthermal reactions of CdCl₂ and thiourea as cadmium and sulphur sources in 1,2-propylene glycol (PG) at 100-200 °C for 10-30 h. Phase and morphology were detected using X-ray diffraction (XRD), and scanning and transmission electron microscopy (SEM, TEM). The products were pure phase of hexagonal wurtzite CdS. The quantitative elemental analysis of Cd:S ratio was detected using energy dispersive X-ray (EDX) analyzer. Raman spectrometer revealed the presence of fundamental and overtone modes at 296 and 595 cm⁻¹, corresponding to the strong 1LO and weak 2LO modes, respectively. Photonic properties were investigated using UV-visible and photoluminescence (PL) spectroscopy. They showed the same absorption at 493-498 nm, and emission at 431 nm due to the excitonic recombination process. A possible formation mechanism was also proposed, according to experimental results.     

Growth of hexagonal prism ZnO nanorods on Zn substrates by hydrothermal method and their photoluminescence

Hexagonal prism ZnO nanorods were successfully grown on Zn substrates by the 120 °C and 24 h hydrothermal reaction of the solutions with pH of 9–12. Results from XRD, SEM, TEM, SAED and HRTEM showed that the as-synthesized products were wurtzite ZnO with the shape of hexagonal prism nanorods grown along the [0 0 1] direction with smooth prismatic side planes. The PL spectra showed strong emission band at 543 nm in the green-yellow region due to the recombination of electrons trapped in singly ionized oxygen vacancies and photoexcited holes. This facile, reproducible and effective low-cost approach is promising for the future large-scale synthesis of wurtzite ZnO nanostructures for different applications in nanotechnology.