Ultraviolet-light-emitting ZnO nanosheets prepared by a chemical bath deposition method

Two-dimensional polar-surface-dominated ZnO nanosheets (nanodiscs) with dimensions of several microns and thickness of tens of nanometres were synthesized in bulk quantity at low temperature (~70??C) by a simple and environmentally benign chemical bath deposition (CBD) method. These ZnO nanosheets are of single-crystal wurtzite structure; they grow along the crystallographic directions within polar {0001} planes. This is different from previous reported films or nanowire arrays prepared by the CBD method. Raman scattering spectrum studies confirm that the as-synthesized nanosheets are of high crystal quality and indicate an optical phonon confinement effect in such ZnO nanosheets. These nanosheets show a sharp intrinsic ultraviolet excitonic emission peak centred at 380?nm at room temperature, have large surface area exposed to the gaseous environment, and could be an ideal ultraviolet light source or objects for the fabrication of nanoscaled devices.

[1]  Sten-Eric Lindquist,et al.  Three-dimensional array of highly oriented crystalline ZnO microtubes , 2001 .

[2]  Bixia Lin,et al.  Green luminescent center in undoped zinc oxide films deposited on silicon substrates , 2001 .

[3]  Takafumi Yao,et al.  Plasma assisted molecular beam epitaxy of ZnO on c -plane sapphire: Growth and characterization , 1998 .

[4]  Masashi Kawasaki,et al.  Growth of ZnO Thin Film by Laser MBE: Lasing of Exciton at Room Temperature , 1997 .

[5]  Schmidt,et al.  Excitation-power dependence of the near-band-edge photoluminescence of semiconductors. , 1992, Physical review. B, Condensed matter.

[6]  Zhong Lin Wang.  Zinc oxide nanostructures: growth, properties and applications , 2004 .

[7]  M. Rajalakshmi,et al.  Optical phonon confinement in zinc oxide nanoparticles , 2000 .

[8]  D. West,et al.  Room‐Temperature Lasing Observed from ZnO Nanocolumns Grown by Aqueous Solution Deposition , 2002 .

[9]  Yuhua Shen,et al.  Structural and optical properties of nanophase zinc oxide , 2003 .

[10]  Junqing Hu,et al.  Two-dimensional micrometer-sized single-crystalline ZnO thin nanosheets , 2003 .

[11]  G. Meng,et al.  Ordered semiconductor ZnO nanowire arrays and their photoluminescence properties , 2000 .

[12]  Masashi Kawasaki,et al.  Ultraviolet spontaneous and stimulated emissions from ZnO microcrystallite thin films at room temperature , 1997 .

[13]  J. MacManus‐Driscoll,et al.  Electrochemical growth of ZnO nanoplates , 2005, Nanotechnology.

[14]  M. Izaki,et al.  Room-Temperature Deposition of Defect-Free Magnetite Film by Chemical Reaction from an Aqueous Solution , 2001 .

[15]  J. Zuo,et al.  Induced growth of asymmetric nanocantilever arrays on polar surfaces. , 2003, Physical review letters.

[16]  Zhong Lin Wang,et al.  Single-crystal hexagonal disks and rings of ZnO: low-temperature, large-scale synthesis and growth mechanism. , 2004, Angewandte Chemie.

[17]  Dapeng Yu,et al.  Optical properties of the ZnO nanotubes synthesized via vapor phase growth , 2003 .

[18]  U. Gösele,et al.  On the growth mechanism and optical properties of ZnO multi-layer nanosheets , 2004 .

[19]  Peidong Yang,et al.  Low-temperature wafer-scale production of ZnO nanowire arrays. , 2003, Angewandte Chemie.

[20]  Yuan Yao,et al.  Well‐Aligned ZnO Nanowire Arrays Fabricated on Silicon Substrates , 2004 .

[21]  Denis L. Rousseau,et al.  First-Order Raman Effect in Wurtzite-Type Crystals , 1969 .

[22]  Bin Chen,et al.  Optical properties of single-crystalline ZnO nanowires on m-sapphire , 2003 .

[23]  Jih-Jen Wu,et al.  Catalyst-Free Growth and Characterization of ZnO Nanorods , 2002 .

[24]  Robert P. H. Chang,et al.  Random laser action in semiconductor powder , 1999 .

[25]  Olga Dulub,et al.  Novel stabilization mechanism on polar surfaces: ZnO(0001)-Zn. , 2003, Physical review letters.

[26]  M. Izaki.  Light-assisted chemical deposition of highly (0001) oriented zinc oxide film. , 2002, Chemical communications.

[27]  Masashi Kawasaki,et al.  Room-temperature ultraviolet laser emission from self-assembled ZnO microcrystallite thin films , 1998 .

[28]  C. Klingshirn,et al.  The Luminescence of ZnO under High One- and Two-Quantum Excitation†‡ , 1975 .

[29]  K. Wong,et al.  Intensity dependence and transient dynamics of donor–acceptor pair recombination in ZnO thin films grown on (001) silicon , 2003 .

[30]  S. Lau,et al.  Polycrystalline ZnO thin films on Si (100) deposited by filtered cathodic vacuum arc , 2001 .

[31]  Yiying Wu,et al.  Room-Temperature Ultraviolet Nanowire Nanolasers , 2001, Science.

[32]  Zhong Lin Wang,et al.  Polar-surface dominated ZnO nanobelts and the electrostatic energy induced nanohelixes, nanosprings, and nanospirals , 2004 .

[33]  Ming Bin Yu,et al.  Zinc oxide nanodisk , 2004 .

[34]  D. Milkie,et al.  Raman studies of semiconducting oxide nanobelts. , 2002, Journal of nanoscience and nanotechnology.

[35]  G. Thornton,et al.  Stability of polar oxide surfaces. , 2001, Physical review letters.