Xiaoli He

Publications (2)8.7 Total impact

• Source

  Available from: nanoarchive.org

  Article: Synthesis of vertically oriented GaN nanowires on a LiAlO2 substrate via chemical vapor deposition

  Xiaoli He, Guowen Meng, Xiaoguang Zhu, Mingguang Kong
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  ABSTRACT: Vertically oriented nanowires (NWs) of single-crystalline wurtzite GaN have been fabricated on γ-LiAlO2 (100) substrate coated with a Au layer, via a chemical vapor deposition process at 1000 °C using gallium and ammonia as source materials. The GaN NWs grow along the nonpolar [10$ \bar 1 $ \bar 1 0] direction with steeply tapering tips, and have triangular cross-sections with widths of 50–100 nm and lengths of up to several microns. The GaN NWs are formed by a vapor-liquid-solid growth mechanism and the tapering tips are attributed to the temperature decrease in the final stage of the synthesis process. The aligned GaN NWs show blue-yellow emission originating from defect levels, residual impurities or surface states of the GaN NWs, and have potential applications in nanotechnology.
  Nano Research 04/2012; 2(4):321-326. · 6.97 Impact Factor
• Article: Structure and magnetic properties of CoNiP nanowire arrays embedded in AAO template

  Xiaoli He, Guangbing Yue, Yufeng Hao, Qiaoling Xu, Qing Wei, Xiaoguang Zhu, Mingguang Kong, Lide Zhang, Xing Li
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  ABSTRACT: Ternary CoNiP nanowire (NW) arrays have been synthesized by electrochemical deposition inside the nanochannels of anodic aluminum oxide (AAO) template. The CoNiP NWs deposited at room temperature present soft magnetic properties, with both parallel and perpendicular coercivities less than 500 Oe. In contrast, as the electrolyte temperature (Telc) increases from 323 to 343 K, the NWs exhibit hard magnetic properties with coercivities in the range of 1000–2500 Oe. This dramatic increase in coercivities can be attributed to the domain wall pinning that is related to the formation of Ni and Co nanocrystallites and the increase of P content. The parallel coercivity (i.e. the applied field perpendicular to the membrane surface) maximum as high as 2500 Oe with squareness ratio up to 0.8 is achieved at the electrolyte temperature of 328 K. It has been demonstrated that the parallel coercivity of CoNiP NWs can be tuned in a wide range of 200–2500 Oe by controlling the electrolyte temperature, providing an easy way to control magnetic properties and thereby for their integration with magnetic-micro-electro-mechanical systems (MEMS).
  Journal of Crystal Growth 310(15):3579-3583. · 1.73 Impact Factor