Flower-like ZnO hollow microspheres loaded with CdO nanoparticles as high performance sensing material for gas sensors

Abstract CdO decorated flower-like ZnO hollow microspheres were successfully prepared via a two-step hydrothermal strategy. CdO nanoparticles (∼12 nm) equably loaded on the surfaces of ZnO nanosheets, which could be clearly observed from SEM and TEM images. The results of X-ray photoelectron spectroscopy and H 2 temperature-programmed reduction (H 2 -TPR) indicated that the amount of chemisorbed oxygen was increased after the introduction of CdO nanoparticles. Compared with the flower-like ZnO hollow microspheres, the 2.6 mol% CdO:ZnO heterostructure composites exhibited highest response (65.5) to 100 ppm ethanol at 250 °C, which was about 16 folder higher than that of pure ZnO at the same operating temperature of 250 °C. Significantly, the detection limit of the 2.6 mol% CdO:ZnO heterostructure could reach ppb level (500 ppb). The mechanism of the enhanced ethanol sensing was also discussed systematically.

[1]  Y. Alhamed,et al.  Partial oxidation of methanol over Au/CeO2–ZrO2 and Au/CeO2–ZrO2–TiO2 catalysts , 2016 .

[2]  A. Fernández,et al.  Transparent conducting CdO films formed by chemical bath deposition , 1993 .

[3]  B. Tichenor,et al.  Destruction of volatile organic compounds via catalytic incineration (journal version) , 1987 .

[4]  Jong‐Heun Lee,et al.  Transformation of ZnO nanobelts into single-crystalline Mn3O4 nanowires. , 2012, ACS applied materials & interfaces.

[5]  S. Jiménez-Sandoval,et al.  High transmittance CdO thin films obtained by the sol-gel method , 2000 .

[6]  Bingqiang Cao,et al.  Direct hydrothermal growth of ZnO nanosheets on electrode for ethanol sensing , 2014 .

[7]  J. Archana,et al.  Influence of substrate temperature on ethanol sensing properties of CdO thin films prepared by facile spray pyrolysis method , 2015, Journal of Materials Science: Materials in Electronics.

[8]  Dazhi Wang,et al.  Co-nanocasting synthesis of Cu based composite oxide and its promoted catalytic activity for methanol steam reforming , 2016 .

[9]  Peng Sun,et al.  Low operating temperature toluene sensor based on novel α-Fe2O3/SnO2 heterostructure nanowire arrays , 2016 .

[10]  Ning Han,et al.  CdO activated Sn-doped ZnO for highly sensitive, selective and stable formaldehyde sensor , 2011 .

[11]  Yoshitake Masuda,et al.  In2O3–SnO2 nano-toasts and nanorods: Precipitation preparation, formation mechanism, and gas sensitive properties , 2009 .

[12]  Song Qiu,et al.  Synthesis of nestlike ZnO hierarchically porous structures and analysis of their gas sensing properties. , 2012, ACS applied materials & interfaces.

[13]  Yan Wang,et al.  Isopropanol sensing properties of coral-like ZnO–CdO composites by flash preparation via self-sustained decomposition of metal–organic complexes , 2014 .

[14]  Kijung Yong,et al.  Fabrication of ZnO/CdS, ZnO/CdO core/shell nanorod arrays and investigation of their ethanol gas sensing properties , 2016 .

[15]  Peng Sun,et al.  Highly Enhanced Sensing Properties for ZnO Nanoparticle-Decorated Round-Edged α-Fe₂O₃ Hexahedrons. , 2015, ACS applied materials & interfaces.

[16]  B. Reedy,et al.  Temperature modulation in semiconductor gas sensing , 1999 .

[17]  J. H. Lee,et al.  Ultraselective and ultrasensitive detection of H2S in highly humid atmosphere using CuO-loaded SnO2 hollow spheres for real-time diagnosis of halitosis , 2014 .

[18]  Zhengfei Dai,et al.  Honeycomb-like periodic porous LaFeO₃ thin film chemiresistors with enhanced gas-sensing performances. , 2014, ACS applied materials & interfaces.

[19]  Xiumei Xu,et al.  One-step synthesis and gas sensing properties of hierarchical Cd-doped SnO2 nanostructures , 2014 .

[20]  Ali Reza Mahjoub,et al.  Synthesis and gas-sensing properties of nano- and meso-porous MoO3-doped SnO2 , 2010 .

[21]  Jinyun Liu,et al.  Shape- and phase-controlled synthesis of In2O3 with various morphologies and their gas-sensing properties , 2009 .

[22]  Huiqing Fan,et al.  NiO/ZnO p–n heterostructures and their gas sensing properties for reduced operating temperature , 2016 .

[23]  H. Fan,et al.  Room-temperature solid state synthesis of ZnO/α-Fe2O3 hierarchical nanostructures and their enhanced gas-sensing properties , 2012 .

[24]  P. Patil,et al.  Ethanol sensing properties of chemosynthesized CdO nanowires and nanowalls , 2011 .

[25]  J. Rayappan,et al.  Nanostructured mixed ZnO and CdO thin film for selective ethanol sensing , 2012 .

[26]  Derek R. Miller,et al.  Nanoscale metal oxide-based heterojunctions for gas sensing: A review , 2014 .

[27]  Shuyi Ma,et al.  Synthesis of SnO2–ZnO heterostructured nanofibers for enhanced ethanol gas-sensing performance , 2015 .

[28]  N. Yamazoe,et al.  Hollow zinc oxide microspheres functionalized by Au nanoparticles for gas sensors , 2014 .

[29]  Kijung Yong,et al.  CuO/ZnO Heterostructured Nanorods: Photochemical Synthesis and the Mechanism of H2S Gas Sensing , 2012 .

[30]  Ravinder Singh,et al.  Temperature dependent selective and sensitive terbium doped ZnO nanostructures , 2016 .

[31]  Soumen Das,et al.  SnO2: A comprehensive review on structures and gas sensors , 2014 .

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

[33]  J. H. Lee,et al.  Enhanced ethanol sensing characteristics of In2O3-decorated NiO hollow nanostructures via modulation of hole accumulation layers. , 2014, ACS applied materials & interfaces.

[34]  Jie-Sheng Chen,et al.  Porous titania with heavily self-doped Ti3+ for specific sensing of CO at room temperature. , 2013, Inorganic chemistry.

[35]  M. Cao,et al.  Synthesis and enhanced ethanol sensing properties of α-Fe2O3/ZnO heteronanostructures , 2009 .

[36]  Peng Sun,et al.  Microwave assisted synthesis of hierarchical Pd/SnO2 nanostructures for CO gas sensor , 2016 .

[37]  Peng Sun,et al.  Hydrothermal preparation and gas sensing properties of Zn-doped SnO2 hierarchical architectures , 2014 .

[38]  G. Lu,et al.  Preparation of Ag-loaded mesoporous WO3 and its enhanced NO2 sensing performance , 2016 .

[39]  R. C. King,et al.  Handbook of X Ray Photoelectron Spectroscopy: A Reference Book of Standard Spectra for Identification and Interpretation of Xps Data , 1995 .

[40]  Zhihao Yuan,et al.  Nanopillar ZnO gas sensor for hydrogen and ethanol , 2007 .

[41]  Zhen-Lai Zhou,et al.  Effects of calcining temperature on the phase structure and the formaldehyde gas sensing properties of CdO-mixed In2O3 , 2008 .

[42]  P. Gouma,et al.  An overview of the translation of selective semiconducting gas sensors from first results to automotive exhaust gas monitors to a platform for breath-based diagnostics , 2015 .

[43]  Hongwen Zhang,et al.  In situ growth of porous ZnO nanosheet-built network film as high-performance gas sensor , 2015 .

[44]  Thorsten Wagner,et al.  Mesoporous materials as gas sensors. , 2013, Chemical Society reviews.

[45]  P. Patil,et al.  Gas sensing performance of the spray deposited Cd-ZnO thin films , 2014 .

[46]  N. Yamazoe,et al.  Surface chemistry of neat tin oxide sensor for response to hydrogen gas in air , 2016 .

[47]  Xiaoping Shen,et al.  α‐Fe2O3 nanospindles loaded with ZnO nanocrystals: Synthesis and improved gas sensing performance , 2014 .

[48]  János Mizsei,et al.  How can sensitive and selective semiconductor gas sensors be made , 1995 .

[49]  Haiyan Song,et al.  Enhanced ethanol sensing properties of ZnO-doped porous SnO2 hollow nanospheres , 2013 .

[50]  Y. Lei,et al.  Preparation, characterization and application of novel conductive NiO–CdO nanofibers with dislocation feature , 2012 .

[51]  Sheikh A. Akbar,et al.  Gas Sensors Based on One Dimensional Nanostructured Metal-Oxides: A Review , 2012, Sensors.

[52]  G. Lu,et al.  Template-free synthesis and gas sensing properties of hierarchical hollow ZnO microspheres , 2013 .

[53]  Zeng Wen,et al.  Gas-sensing properties of SnO2–TiO2-based sensor for volatile organic compound gas and its sensing mechanism , 2010 .

[54]  W. Wlodarski,et al.  Nanorod based Schottky contact gas sensors in reversed bias condition , 2010, Nanotechnology.

[55]  D. Gonbeau,et al.  Systematic XPS studies of metal oxides, hydroxides and peroxides , 2000 .

[56]  G. Neri,et al.  CO sensing characteristics of hexagonal-shaped CdO nanostructures prepared by microwave irradiation , 2012 .

[57]  P. Patil,et al.  From nanowires to cubes of CdO: Ethanol gas response , 2011 .

[58]  E. Gulari,et al.  Effect of catalyst preparation on Au/Ce1−xZrxO2 and Au–Cu/Ce1−xZrxO2 for steam reforming of methanol , 2013 .

[59]  Meihong Fan,et al.  Porous nanoplate-assembled CdO/ZnO composite microstructures: A highly sensitive material for ethanol detection , 2014 .

[60]  Jun Zhang,et al.  ZnO hollow spheres: Preparation, characterization, and gas sensing properties , 2009 .

[61]  J. Y. Chiou,et al.  Effect of Co, Fe and Rh addition on coke deposition over Ni/Ce0.5Zr0.5O2 catalysts for steam reforming of ethanol , 2014 .

[62]  Il-Doo Kim,et al.  Advances and new directions in gas-sensing devices , 2013 .

[63]  H Zhao,et al.  Low concentration H2S detection of CdO-decorated hierarchically mesoporous NiO nanofilm with wrinkle structure , 2016 .

[64]  Xi‐Wen Du,et al.  CdO nanoflake arrays on ZnO nanorod arrays for efficient detection of diethyl ether , 2016 .

[65]  J. Morante,et al.  Micromachined twin gas sensor for CO and O2 quantification based on catalytically modified nano-SnO2 , 2006 .