Sun et al. Nanoscale Research Letters 2011, 6:556 http://www.nanoscalereslett.com/content/6/1/556 Received: 2 June 2011 Accepted: 17 October 2011 Published: 17 October 2011 References 1. Sirbuly DJ, Law M, Yan H, Yang P: Semiconductor nanowires for subwavelength photonics integration. J Phys Chem B 2005, 109:15190-15213. 2. Fang X, Gautamy UK, Bando Y, Golberg D: One-dimensional ZnS-based hetero-, core/shell and hierarchical nanostructures. J Mater Sci Technol 2008, 24:520-528. 3. Appell D: Nanotechnology: wired for success. Nature 2002, 419:553-555. 4. Duan XF, Huang Y, Cui Y, Wang JF, Lieber CM: Indium phosphide nanowires as building blocks for nanoscale electronic and optoelectronic devices. Nature 2001, 409:66-69. 5. He JH, Ho CH: The study of electrical characteristics of heterojunction based on ZnO nanowires using ultrahigh-vacuum conducting atomic force microscopy. Appl Phys Lett 2007, 91:233105. 6. He JH, Hsin CL, Liu J, Chen LJ, Wang ZL: Piezoelectric gated diode of a single ZnO nanowire. Adv Mater 2007, 19:781-784. 7. He JH, Lin YH, McConney ME, Tsukruk VV, Wang ZL, Bao G: Enhancing UV photoconductivity of ZnO nanobelt by polyacrylonitrile functionalization. J Appl Phys 2007, 102:084303. 8. Yan C, Liu J, Liu F, Wu J, Gao K, Xue D: Tube formation in nanoscale materials. Nanoscale Res Lett 2008, 3:473-480. 9. Ozgur U, Alivov YI, Liu C, Teke A, Reshchikov MA, Dogan S, Avrutin V, Cho SJ, Morkocd H: A comprehensive review of ZnO materials and devices. J Appl Phys 2005, 98:041301. 10. Jagadish C, Pearton SJ: Zinc Oxide Bulk, Thin Films and Nanostructures: Processing, Properties and Application Oxford: Elsevier; 2006. 11. Wu J, Xue D: Progress of science and technology of ZnO as advanced material. Science of Advanced Materials 2011, 3:127-149. 12. Huo KF, Hu YM, Fu JJ, Wang XB, Chu PK, Hu Z, Chen Y: Direct and large- area growth of one-dimensional ZnO nanostructures from and on a brass substrate. J Phys Chem C 2007, 111:5876-5881. 13. Wang XD, Song JH, Liu J, Wang ZL: Direct-current nanogenerator driven by ultrasonic waves. Science 2007, 316:102-105. 14. Law M, Greene LE, Johnson JC, Saykally R, Yang PD: Nanowire dye- sensitized solar cells. Nat Mater 2005, 4:455-459. 15. Huang MH, Mao S, Feick H, Yan HQ, Wu YY, Kind H, Weber E, Russo R, Yang PD: Room-temperature ultraviolet nanowire nanolasers. Science 2001, 292:1897-1899. 16. He JH, Hsu JH, Wang CW, Lin HN, Chen LJ, Wang ZL: Pattern and feature designed growth of ZnO nanowire arrays for vertical devices. J Phys Chem B 2006, 110:50-53. 17. Travnikov VV, Freiberg A, Savikhin SF: Surface excitons in ZnO crystals. J Lumin 1990, 47:107-112. 18. Savikhin S, Freiberg A: Origin of “universal” ultraviolet luminescence from the surfaces of solids at low temperatures. J Lumin 1993, 55:1-3. 19. Wischmeier L, Voss T, Borner S, Schade W: Comparison of the optical properties of as-grown ensembles and single ZnO. Appl Phys A 2006, 84:111-116. 20. Shimpi P, Gao PX, Goberman D, Ding Y: Low temperature synthesis and characterization of MgO/ZnO composite nanowire arrays. Nanotechnology 2009, 20:125608. 21. Vanheusden K, Warren WL, Seager CH, Tallant DR, Voigt JA, Gnade BE: Mechanisms behind green photoluminescence in ZnO phosphor powders. J Appl Phys 1996, 79:7983-7990. 22. Li D, Leung YH, Djurisic AB, Liu ZT, Xie MH, Shi SL, Xu SJ, Chan WK: Different origins of visible luminescence in ZnO nanostructures fabricated by the chemical and evaporation methods. Appl Phys Lett 2004, 85:1601-1603. 23. Hsu NE, Hung WK, Chen YF: Origin of defect emission identified by polarized luminescence from aligned ZnO nanorods. J Appl Phys 2004, 96:4671-4673. 24. Kärber E, Raadik T, Dedova T, Krustok J, Mere A, Mikli V, Krunks M: Photoluminescence of spray pyrolysis deposited ZnO nanorods. Nanoscale Res Lett 2011, 6:359. 25. Park WI, Yoo J, Kim DW, Yi GC: Fabrication and photoluminescent properties of heteroepitaxial ZnO/Zn0.8Mg0.2O coaxial nanorod heterostructures. J Phys Chem B 2006, 110:1516-1519. Page 8 of 8 26. Li SZ, Gan CL, Cai H, Yuan CL, Guo J, Lee PS, Ma J: Enhanced photoluminescence of ZnO/Er2O3 core-shell structure nanorods synthesized by pulsed laser deposition. Appl Phys Lett 2007, 90:263106. 27. Richters JP, Voss T, Skim D, Scholz R, Zacharias M: Enhanced surface- excitonic emission in ZnO/Al2O3 core-shell nanowires. Nanotechnology 2008, 19:305202. 28. Soci C, Zhang A, Xiang B, Dayeh SA, Aplin DPR, Park J, Bao XY, Lo YH, Wang D: ZnO nanowire UV photodetector with high internal gain. Nano Lett 2007, 7:1003-1009. 29. Lu HB, Li H, Liao L, Tian Y, Shuai M, Li JC, Hu MF, Fu Q, Zhu BP: Low- temperature synthesis and photocatalytic properties of ZnO nanotubes by thermal oxidation of Zn nanowires. Nanotechnology 2008, 19:045605. 30. Yin M, Gu Y, Kuskovsky IL, Andelman T, Zhu Y, Neumark GF, O’Brien S: Zin oxide quantum rods. J Am Chem Soc 2004, 126:6206-6207. 31. Yang WC, Wang CW, He JH, Chang YC, Wang JC, Chen LJ, Chen HY, Gwo S: Facile synthesis of large scale Er-doped ZnO flower-like structures with enhanced 1.54 μm infrared emission. Phys Status Solidi A 2008, 205:1190-1195. 32. Greene LE, Yuhas BD, Law M, Zitoun D, Yang PD: Solution-grown zinc oxide nanowires. Inorg Chem 2006, 45:7535-7543. 33. Chen HC, Chen MJ, Liu TC, Yang JR, Shiojiri M: Structure and stimulated emission of a high-quality zinc oxide epilayer grown by atomic layer deposition on the sapphire substrate. Thin Solid Films 2010, 519:536-540. 34. Shih YT, Wu MK, Li WC, Kuan H, Yang JR, Shiojiri M, Chen MJ: Amplified spontaneous emission from ZnO in n-ZnO/ZnO nanodots-SiO2 composite/p-AlGaN heterojunction light-emitting diodes. Nanotechnology 2009, 20:165201. 35. Chen MJ, Shih YT, Wu MK, Tsai FY: Enhancement in the efficiency of light emission from silicon by a thin Al2O3 surface-passivating layer grown by atomic layer deposition at low temperature. J Appl Phys 2007, 101:033130. 36. Shalish I, Temkin H, Narayanamurti V: Size-dependent surface luminescence in ZnO nanowires. Phys Rev B 2004, 69:245401. 37. Chen CY, Lin CA, Chen MJ, Lin GR, He JH: ZnO/Al2O3 core-shell nanorod arrays: growth, structural characterization, and luminescent properties. Nanotechnology 2009, 20:185605. 38. Vanheusden K, Seager CH, Warren WL, Tallant DR, Voigt JA: Correlation between photoluminescence and oxygen vacancies in ZnO phosphors. Appl Phys Lett 1996, 68:403-405. 39. Weber DH, Beyer A, Völkel B, Gölzhäuser A, Schlenker E, Bakin A, Waag A: Determination of the specific resistance of individual freestanding ZnO nanowires with the low energy electron point source microscope. Appl Phys Lett 2007, 91:253126. 40. Muth JF, Kolbas RM, Sharma AK, Oktyabrsky S, Narayan J: Excitonic structure and absorption coefficient measurements of ZnO single crystal epitaxial films deposited by pulsed laser deposition. J Appl Phys 1999, 85:7884-7887. 41. Dijken AV, Meulenkamp EA, Vanmaekelbergh D, Meijerink A: The kinetic of the radiative and nonradiative processes in nanocrystalline ZnO particles upon photoexcitation. J Phys Chem B 2000, 104:1715-1723. doi:10.1186/1556-276X-6-556 Cite this article as: Sun et al.: Improved characteristics of near-band-edge and deep-level emissions from ZnO nanorod arrays by atomic-layer- deposited Al2O3 and ZnO shell layers. Nanoscale Research Letters 2011 6:556. Submit your manuscript to a journal and beneﬁt from: 7 Convenient online submission 7 Rigorous peer review 7 Immediate publication on acceptance 7 Open access: articles freely available online 7 High visibility within the ﬁeld 7 Retaining the copyright to your article Submit your next manuscript at 7 springeropen.com