Growth and characterization of ZnO cross-like structures by hydrothermal method

Abstract

ZnO cross-like structures has been synthesized by a cetyltrimethylammonioum hydroxide (CTAOH)-assisted hydrothermal method at low temperature (60 0 C) as a function of the CTAOH concentration. The structure and morphology of the structures ZnO cross-like were studied by means of x-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), and scanning electron microscopy (SEM).Keywords: Zinc oxide, cross-like nanostructures, assisted hydrothermal method. INTRODUCTIONThe low dimensional, binary semiconductor oxide ZnO has distinctive properties: optically, ZnO is a wide-band-gap (3.37eV) at room temperature, compound that is promising for short-wavelength optoelectronic applications [1]. Its large excitation energy (60meV) can ensure an efficient excitonic emission at room temperature and ultraviolet (UV) luminescence has been reported in disordered nanoparticles and thin films [2][3][4][5][6][7][8]. ZnO is a uniquely structured material: is a hexagonal wurtzite-structured oxide, where each anion (O -2 ) is surrounded by four cations (Zn +2) at the corners of a tetrahedron and vice versa. Since the Wurtzite no possess an centre of symmetry, the crystal exhibits crystallographic polarity whose polar axis is the c-axis; ZnO have two polar-surfaces {0001}, and it belongs to the C 6 4 v space group.With this properties ZnO has been synthesized in a great diversity of nanostructures, including nanosprings [9] [16] synthesized efficiently due to the high ionicity of the polar surfaces [9,10].In this work, using a cetyltrimethylammonioun hydroxide-assisted hydrothermal method, ZnO crosslike structures were synthesized as a function of CTAOH concentration. The structural and morphological properties of this structures as-grown have been analyzed. EXPERIMENTAL Preparation of cross-like structuresThe chemicals precursors used in this study were analytical reagent grade (Sigma-Aldrich) and used without further purification.Zinc acetate [Zn(CH 3 COO) 2 ] was used as precursor and cetyltrimethylammonioum hydroxide (CTAOH) as surfactant and catalyst. Initially, 0.01M of zinc acetate was dissolved in ethyl alcohol and magnetically stirred at 60 0 C for 1h. The concentration of [Zn(CH 3 COO) 2 ] was maintained constant for all reactions. Then, cetyltrimethylammonioun hydroxide was mixed into the solution with Zn 2+ /CTAOH molar

Optimizing photo-mineralization of aqueous methyl orange by nano-ZnO catalyst under simulated natural conditions

“…3 . The other two emission peaks at ~445 nm and ~483 nm are attributed to the presence of oxygen vacancies which cause crystal imperfections, as reported earlier [ 42 ]. The value of the band gap is not far different from that measured by electronic absorption spectra discussed above.…”

Correlation of Filtration Behavior of Chiral and Racemic Mg(tartrate) Suspensions with Morphological Differences and Observation of Cross Structure in a Metal Organic Framework

“…The lengths of the horizontal and vertical shafts in one of these crosses both measured 7.5 μm and all the four arms were equal in length, i.e., the structure was in the form of a Greek cross . Cross structures, with arms in the shape of petals, have been reported previously for cetyltrimethylammonium hydroxide-assisted hydrothermal synthesis of ZnO from Zn­(CH 3 COO) 2 at 60 °C temperature . Cross structures of submicron dimension have also been observed in a study on magnetite Fe 3 O 4 preparation by an arc-electrodeposition technique .…”

Modified structural, surface morphological and optical studies of Li3+ swift heavy ion irradiation on zinc oxide nanoparticles

“…1 Zinc oxide has a polar hexagonal axis, the c-axis, which is parallel to z(0001). [2][3][4][5] The structure of zinc oxide can be basically illustrated as a number of sporadic planes composed of O 2À and Zn 2+ ions, stacked in an alternating sequence along the c-axis. The hexagonal unit cell has two lattice parameters, 'a' and 'c', in the ratio of c/a ¼ 1.633 and belongs to the space group symmetry of P6 3 mc -C 4 6v (a ¼ 0.3296 and c ¼ 0.52065 nm).…”