By continuing to use this site you agree to our use of cookies. Structural and morphology of zno nanorods synthesized. In this study, four types of standardized zno nanoparticles were prepared for assessment of their potential biological risk. N species concerns its exceptionally high concentration of zinc vacancies, as great as 17%, i. Journal of nanomaterials hindawi publishing corporation. The wurtzite structure family has a few important members, such as zno, gan, aln, zns, and cdse, which are important materials for applications in optoelectronics, lasing, and piezoelectricity.
Pdf the development of technologically important material zincblende zno has been hindered due to the. Zno crystal has a wurtzite structure with c6v symmetry arxiv. The wurtzite structure may be considered as an hcp structure with a basis of two atoms. Multiple datasets can be downloaded as individual files inside a zip archive by selecting the datasets and then clicking. Taking into account the so interaction, the energy bands of zno can be calculated by the epm. Rs analysis has revealed that the unmodified zno and carbon modified zno samples have characteristic raman optic modes at 325 cm. The nanocrystals of zno with hexagonal wurtzite structure were characterized by xray powder diffraction xrd, transmission electron microscopy tem, scanning electron microscopy sem, uvvis absorption and ftir spectroscopy techniques.
The wurtzite structure has an abab hexagonal close packing hcp structure. The synthesized nanoparticles retained the wurtzite hexagonal structure, which was confirmed by xray diffraction studies. Wurtzite nio wnio has been found to display halfmetallicity. Multiple datasets can be concatenated into a single downloadable file by selecting the datasets and then clicking. The raman spectrum measurement result is comparable with that of the xrd analysis, which shows a single peak at 002 corresponding to the wurtzite structure of zno. It can be considered as being formed by the penetration of two hcp lattices see fig. Firstprinciples study on zno nanoclusters with hexagonal prism structures. To unravel this enigma, we have re investigated the synthesis of undoped zincdeficient zinc oxide nanoparticles. Zinc oxide zno is a wellknown wide band gap semiconductor 3. These compounds have recently received considerable attention due to their potential in the semiconductor industry. Draw wurtzite crystal structure with vesta zno example easyedu.
The wurtzite structure of zno crystal has c6v symmetry. Ke1,2,a 1school of physics and nuclear energy engineering, beihang university, beijing 100191, peoples republic of china 2lnm, institute of mechanics, chinese academy of sciences, beijing 100190, peoples republic of china. In recent years, zinc oxide zno has attracted a lot of. The asprepared specimen exhibits strong ultraviolet exciton emission at 385 nm and disappearance of visible defect emission.
The investigations were conducted by xray absorption fine structure spectroscopy xafs technique for the samples prepared with different heating and doping processes. In a real zno crystal, the wurtzite structure deviates from the ideal arrangement. The two important characteristics of the wurtzite structure are the noncentral symmetry and polar surfaces. This structure is a member of the hexagonal crystal system and consists of tetrahedrally coordinated zinc and sulfur atoms that are stacked in an ababababab pattern. The wurtzite structure is a hexagonal lattice in which each zn. A convenient route at ambient conditions was employed to prepare narrowdispersed zno nanorods in terms of size and morphology. Structures of wurtzite zno solid solutions with mgo and. Powderphased zno nanoparticles with different particle sizes 20 nm and 100 nm were coated with citrate or lserine to induce a. Multiwavelength raman scattering of nanostructured al. Pdf firstprinciples study on zno nanoclusters with.
Wurtzitetotetragonal structure phase transformation and size effect in zno nanorods j. The zinc blende zno structure is metastable and can be stabilized only by heteroepitaxial growth on cubic substrates, such as zns 5, gaaszns 6, and. All the powder diffraction peaks could be indexed to the hexagonal wurtzite structure of zno, which was further confirmed from the jcpds no. To find out more, see our privacy and cookies policy. Xray diffraction xrd pattern reveals wurtzite structure of zno nanoparticles. In this work, we studied the crystal structure of radially overgrown gaas wurtzite 2h nws, especially the resulting crystal structure as nws progressively grow into each other and merge. Phase transformation in radially merged wurtzite gaas. Wurtzite lattice parameters such as the values of d, the distance between adjacent planes in the miller. Wurtzite zinc oxide has a hexagonal structure space group c6mc with lattice.
The physical and chemical properties of wurtzite zno wzno has been extensively. Pure zno and cobalt co doped zno nanoparticles nps were synthesized by the coprecipitation method. Physicochemical properties of surface chargemodified zno. Xray diffraction xrd pattern refers polycrystalline nature with a hexagonal structure.
Xray peak broadening analysis of zno nanoparticles. From fesem studies, zno and co doped zno nps showed spherical and nanorod mixed phase and spherical like morphology, respectively. It is found that the electron states are either twofold or fourfold degenerate. The structural properties of wurtzite and rocksalt mgxzn1. Abstract this chapter starts with an overview of the zno crystal structure and its.
Rietveld refinement carried out by fullprof software of xrd patterns a provide accurate values. All evident peaks could be indexed as the zno wurtzite structure jcpds data card no. Compound semiconductors with zincblende or wurtzitetype structureswhere each atom of one element is in 4fold and tetrahedral coordination to atoms of the other element. Piezoelectric,optical and electrical characterization of. Among the binary oxide semiconductors, zno is the only material with a wurtzitetype structure that has a. Crystal and electronic structure study of mn doped.
Zno nps have characteristic peaks of hexagonal wurtzite zno structure. In addition to the nitrogen doping, the main characteristic of this zno. Rod shape of zno nanoparticles of average particle size 10. Wurtzite zincoxide wzno is a wide bandgap semiconductor that holds promise in power electronics applications, where heat dissipation is. Zno zinc blende unit cell the hexagonal structure of zinc oxide zno has a point group 6 mm in hermannmauguin notation or c6vin reported space group is generally p63mc or c6v4. The wurtzite structure is most stable and thus most common at ambient conditions. Wurtzitetotetragonal structure phase transformation and.
The wurtzite structure of zno can be considered to be composed of two. The wurtzite crystal structure, named after the mineral wurtzite, is a crystal structure for various binary compounds. Its crystal structure is called the wurtzite crystal structure, to which it lends its name. We investigated the properties of vibrational modes of the semiconductors such as zno, gan and 6hsic belonging to the wurtzite structure in order to characterize the materials.
Wurtzite structure of zno nanoparticles is belonging to space group. In the extreme case u 12 this structure becomes the b k bn structure. Synthesis and characterization of zno nanoparticles. With an exciton binding energy of 60 mev and wide direct. Zinc oxide zno is a wide band gap semiconductor with an energy gap of 3. Thus, hcp clusters can attain their preference with respect to mtps comprising fcc fragments and optimized fcc clusters only for very large sizes. Transmission electron microscopy and xray diffraction were used to characterize the structurally uniform and wellproportioned products. Crystal structure, chemical binding, and lattice properties. Introduction zinc oxide zno is a iivi compound semiconductor having wide band gap of 3. Electronic structure of zno wurtzite quantum wires.
The natural crystal structure of zno is the hexagonal wurtzite structure. Structures of wurtzite zno solid solutions with mgo and cdo by first principles calculations zhijun wang 1,2 and isao tanaka1,3 1 department of materials science and engineering, kyoto university, kyoto, 6068501, japan 2physics department, jilin university, changchun, jilin, 026, china 3 nanostructures research laboratory, japan fine ceramics center, nagoya, 4568587, japan. The electronic structure and optical properties of zno wurtzite quantum wires with radius r. Unravelling the origin of the giant zn deficiency in. Thermal conductivity of wurtzite zincoxide from first. Regularly shaped, singlecrystalline zno nanorods with. Zno nanoparticles were synthesized by microemulsion route in ws ratio of 5 at room temperature.
Draw wurtzite crystal structure with vesta zno example. Electronic structures of wurtzite zno and zno mgzno. The wurtzite crystal structure of zno with the lattice parameters a and c indicated in a, and the calculated band structure of zno using the hse hybrid functional in b. The change in the crystal and electronic structure properties of wurtzite zno nanoparticles was studied according to mn doping in the powder samples. In the recent era zinc oxide nanoparticles attracted the researchers due.
The two hcp lattices have the same axis a 3 axis but one of them is displaced with respect to the other. We observed that the freestanding gaas nws retain the pure 2h. We characterized the grown structure by high resolution xrd and tem with diffraction analysis. Combining microelectromechanical system mems technology with selfassembled. Synthesis, structural and optical properties of pure zno. The zinc blend form can be stabilized by please purchase pdf split merge on. Structural and optoelectronic properties of unsaturated zno and. We use cookies to offer you a better experience, personalize content, tailor advertising, provide social media features, and better understand the use of our services. Structural and optical characterization of zno nanoparticles synthesized by microemulsion route harish kumar. The energy of the valenceband maximum vbm was set to zero.
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