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Harnack O, Pacholski C, Weller H, Yasuda A, Wessels JM: Rectifying behavior of electrically aligned ZnO nanorods. Nano Lett 2003, 3:1097–1101. doi:10.1186/1556-276X-7-246 Cite this article as: Wang et al.: Controllable growth of ZnO nanorod arrays with different densities and their photoelectric properties. Nanoscale Research Letters 2012 7:246. 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