Bi-functional mechanism of H2S detection using CuO–SnO2 nanowires

In this study, a bi-functional mechanism is proposed and validated, which may be used to explain all of the reported experimental observations and to predict new sensing control parameters. Fast response and recovery in H2S sensing was then realized by using bi-functional SnO2 nanowires which have been radially modulated with CuO. Firstly, Cu metal nanoparticles were synthesized by applying γ-ray radiolysis. The Cu nanoparticles (attached to the surface of the SnO2 nanowires) were oxidized to the CuO phase by a thermal treatment at 500 °C in air. The H2S sensing characteristics of the CuO-functionalized SnO2 nanowires were compared with those of bare SnO2 nanowires. The results demonstrated that γ-ray radiolysis is an effective means of functionalizing the surface of oxide nanowires with CuO nanoparticles, and CuO functionalization greatly enhanced the ability of the SnO2 nanowires to detect H2S in terms of the response and recovery times. In addition, two control parameters, a 0.5 CuO to SnO2 surface ratio and a sensing temperature range of 80–220 °C, are predicted. The radially modulated nanostructures achieve two functions: (1) the formation and break-away of p–n (CuO–SnO2) junctions, and (2) the formation and dissolution of CuS using CuO–SnO2 solid solutions.

[1]  D. Scanlon,et al.  On the possibility of p-type SnO2 , 2012 .

[2]  P. S. Shewale,et al.  Influence of core temperature on physical and H2S sensing properties of zinc oxide thin films , 2012 .

[3]  S. S. Kim,et al.  Platinum nanoparticle-functionalized tin dioxide nanowires via radiolysis and their sensing capability , 2012 .

[4]  S. S. Kim,et al.  H2S sensing performance of electrospun CuO-loaded SnO2 nanofibers , 2012 .

[5]  J. Park,et al.  Improvement in sensing properties of SnO2 nanowires by functionalizing with Pt nanodots synthesized by gamma-ray radiolysis. , 2012, Journal of nanoscience and nanotechnology.

[6]  J. Park,et al.  Tailoring the Number of Junctions per Electrode Pair in Networked ZnO Nanowire Sensors , 2011 .

[7]  S. S. Kim,et al.  Significant enhancement of the NO2 sensing capability in networked SnO2 nanowires by Au nanoparticles synthesized via γ-ray radiolysis. , 2011, Journal of hazardous materials.

[8]  Byeong Kwon Ju,et al.  Enhanced H2S sensing characteristics of Pt doped SnO2 nanofibers sensors with micro heater , 2011 .

[9]  Sun-Woo Choi,et al.  Junction-Tuned SnO2 Nanowires and Their Sensing Properties , 2011 .

[10]  J. Chiou,et al.  Improved crystalline structure and H2S sensing performance of CuO–Au–SnO2 thin film using SiO2 additive concentration , 2011 .

[11]  Li Zhang,et al.  Electrospun Nanofibers of ZnO−SnO2 Heterojunction with High Photocatalytic Activity , 2010 .

[12]  S. Mathur,et al.  Plasma-Modified SnO2 Nanowires for Enhanced Gas Sensing , 2010 .

[13]  W. Cai,et al.  Metal ion-doped SnO2 ordered porous films and their strong gas sensing selectivity , 2010 .

[14]  J. Park,et al.  Fabrication of a Highly Sensitive Chemical Sensor Based on ZnO Nanorod Arrays , 2009, Nanoscale research letters.

[15]  Byeong Kwon Ju,et al.  Enhanced H2S sensing characteristics of SnO2 nanowires functionalized with CuO , 2009 .

[16]  Victor V. Sysoev,et al.  Percolating SnO2 nanowire network as a stable gas sensor: Direct comparison of long-term performance versus SnO2 nanoparticle films , 2009 .

[17]  Evgheni Strelcov,et al.  Gas sensor based on metal-insulator transition in VO2 nanowire thermistor. , 2009, Nano letters.

[18]  N. K. Gaur,et al.  Copper doped SnO2 nanowires as highly sensitive H2S gas sensor , 2009 .

[19]  A. Walsh,et al.  Energetic and Electronic Structure Analysis of Intrinsic Defects in SnO2 , 2009 .

[20]  Kyung Soo Park,et al.  Gas sensing properties of defect-controlled ZnO-nanowire gas sensor , 2008 .

[21]  Xinyu Xue,et al.  Synthesis and H2S Sensing Properties of CuO-SnO2Core/Shell PN-Junction Nanorods , 2008 .

[22]  Sang Sub Kim,et al.  An approach to fabricating chemical sensors based on ZnO nanorod arrays , 2008, Nanotechnology.

[23]  Young-Jin Choi,et al.  Novel fabrication of an SnO2 nanowire gas sensor with high sensitivity , 2008, Nanotechnology.

[24]  Yadong Li,et al.  High sensitivity of CuO modified SnO2 nanoribbons to H2S at room temperature , 2005 .

[25]  L. A. Patil,et al.  Surface cupricated SnO2-ZnO thick films as a H2S gas sensor , 2004 .

[26]  S. S. Bhatti,et al.  CUO–SNO2 ELEMENT AS HYDROGEN SULFIDE GAS SENSOR PREPARED BY A SEQUENTIAL ELECTRON BEAM EVAPORATION TECHNIQUE , 2003 .

[27]  S. S. Bhatti,et al.  CuO-doped SnO2 thin films as hydrogen sulfide gas sensor , 2003 .

[28]  K. Patil,et al.  High H2S-sensitive copper-doped tin oxide thin film , 2003 .

[29]  Parmanand Sharma,et al.  H2S gas sensing mechanism of SnO2 films with ultrathin CuO dotted islands , 2002 .

[30]  Yoshifumi Yamamoto,et al.  Sensing properties to dilute chlorine gas of indium oxide based thin film sensors prepared by electron beam evaporation , 2002 .

[31]  He Xiuli,et al.  Thin film sensors of SnO2-CuO-SnO2 sandwich structure to H2S , 2001 .

[32]  Wang Li,et al.  H2S sensing properties of the SnO2-based thin films , 2000 .

[33]  Norio Miura,et al.  Dilute hydrogen sulfide sensing properties of CuO–SnO2 thin film prepared by low-pressure evaporation method , 1998 .

[34]  S. Manorama,et al.  Hydrogen sulfide sensor based on tin oxide deposited by spray pyrolysis and microwave plasma chemical vapor deposition , 1994 .

[35]  M. Rumyantseva,et al.  Copper diffusion in SnO2 polycrystalline films , 1994 .

[36]  Norio Miura,et al.  Sensing behavior of CuO-loaded snO2 element for H2S detection , 1991 .