Characterization of structural and electrical properties of ZnO tetrapods

Yu-dong Gu1,2),Wen-jie Mai2,3),and Peng Jiang4) 1) Department of Advanced Materials and Nanotechnology,College of Engineering,Peking University,Beijing 100084,China 2) School of Materials Science and Engineering,Georgia Institute of Technology,Atlanta,Georgia 30332-0245,USA 3) Department of Physics,Jinan University,Guangzhou 510632,China 4) National Center for Nanoscience and Technology,Beijing 100190,China

摘 要：ZnO tetrapods were synthesized by a typical thermal vapor-solid deposition method in a horizontal tube furnace.Structural characterization was carried out by transmission electron microscopy （TEM） and select-area electron diffraction （SAED）,which shows the presence of zinc blende nucleus in the center of tetrapods while the four branches taking hexagonal wurtzite structure.The electrical transport property of ZnO tetrapods was investigated through an in-situ nanoprobe system.The three branches of a tetrapod serve as source,drain,and "gate",respectively;while the fourth branch pointing upward works as the force trigger by vertically applying external force downward.The conductivity of each branch of ZnO-tetrapods increases 3-4 times under pressure.In such situation,the electrical current through the branches of ZnO tetrapods can be tuned by external force,and therefore a simple force sensor based on ZnO tetrapods has been demonstrated for the first time.

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