Room temperature ultra-sensitive resistive humidity sensor based on single zinc oxide nanowire

Abstract A highly sensitive relative humidity (RH) sensor is fabricated by a low-cost and scalable dielectrophoresis method that places a single crystalline zinc oxide nanowire (ZnO NWs) between pre-patterned electrodes in a freestanding device structure. The resistive device demonstrates an exponential sensitivity of more than 5 decades to changes from dry air to 60% RH at room temperature, indebted to a subthreshold carrier modulation due to the high surface-to-volume-ratio and completely exposed NW surface that facilitates surface physisorption of water molecules. Transient and temperature-dependence measurements signify a reproducible sensing performance and an Arrhenius behavior with activation energy of 0.6 eV, expected for these metal oxide semiconductors. These results demonstrate the potential of such nanoscale devices for accurate monitoring of RH in different applications, including fuel cells and automotive sensors, smart clothing, smart food packaging and sensor networks.

[1]  Xiangfeng Duan,et al.  High-yield self-limiting single-nanowire assembly with dielectrophoresis. , 2010, Nature nanotechnology.

[2]  Desheng Jiang,et al.  Zinc oxide nanorod and nanowire for humidity sensor , 2005 .

[3]  Dapeng Yu,et al.  Ultraviolet-emitting ZnO nanowires synthesized by a physical vapor deposition approach , 2001 .

[4]  Charles M. Lieber,et al.  Subthreshold regime has the optimal sensitivity for nanowire FET biosensors. , 2010, Nano letters.

[5]  Dmitri O. Klenov,et al.  Enhanced gas sensing by individual SnO2 nanowires and nanobelts functionalized with Pd catalyst particles. , 2005, Nano letters.

[6]  M. Takata,et al.  Dependence of Electrical Conductivity of ZnO on Degree of Sintering , 1976 .

[7]  P. Servati,et al.  Dielectrophoresis-Assembled ZnO Nanowire Oxygen Sensors , 2011, IEEE Electron Device Letters.

[8]  Y. Qiu,et al.  ZnO Nanotetrapods: Controlled Vapor‐Phase Synthesis and Application for Humidity Sensing , 2007 .

[9]  Zhaoxiong Xie,et al.  High-sensitivity humidity sensor based on a single SnO(2) nanowire. , 2007, Journal of the American Chemical Society.

[10]  T. Nitta.  Development and Application of Ceramic Humidity Sensors , 1988 .

[11]  P. Su,et al.  Humidity sensors based on TiO2 nanoparticles/polypyrrole composite thin films , 2007 .

[12]  Z. M. Rittersma,et al.  Recent achievements in miniaturised humidity sensors—a review of transduction techniques , 2002 .

[13]  S. Soltanian,et al.  Well-aligned zinc oxide nanowire arrays for transparent electrode applications , 2011, IEEE Photonic Society 24th Annual Meeting.

[14]  Jacob Fraden,et al.  Handbook of modern sensors , 1997 .

[15]  Murthy Chavali,et al.  Composite of TiO2 nanowires and Nafion as humidity sensor material , 2006 .

[16]  Enrico Traversa,et al.  Ceramic sensors for humidity detection: the state-of-the-art and future developments , 1995 .

[17]  G. Sberveglieri,et al.  In2O3 nanowires for gas sensors : morphology and sensing characterisation , 2007 .

[18]  Chenglu Lin,et al.  Fabrication and ethanol sensing characteristics of ZnO nanowire gas sensors , 2004 .

[19]  Z. Fan,et al.  ZnO nanowire field-effect transistor and oxygen sensing property , 2004 .

[20]  Y. J. Chen,et al.  Positive temperature coefficient resistance and humidity sensing properties of Cd-doped ZnO nanowires , 2004 .

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

[22]  Chi-En Lu,et al.  Humidity Sensors: A Review of Materials and Mechanisms , 2005 .

[23]  Sheng-Po Chang,et al.  A ZnO nanowire-based humidity sensor , 2010 .

[24]  Noboru Yamazoe,et al.  Humidity sensors: Principles and applications , 1986 .

[25]  C. N. R. Rao,et al.  Sensors for the nitrogen oxides, NO2, NO and N2O, based on In2O3 and WO3 nanowires , 2006 .

[26]  Bin Liu,et al.  Hydrothermal synthesis of ZnO nanorods in the diameter regime of 50 nm. , 2003, Journal of the American Chemical Society.

[27]  Y. Nakata,et al.  Growth mechanism of ZnO nanorods from nanoparticles formed in a laser ablation plume , 2004 .

[28]  Haibin Yang,et al.  Properties of humidity sensing ZnO nanorods-base sensor fabricated by screen-printing , 2008 .

[29]  Tiancheng Wang,et al.  Oxygen sensing characteristics of individual ZnO nanowire transistors , 2004 .