Enhancement of the Humidity Sensing Performance in Mg-Doped Hexagonal ZnO Microspheres at Room Temperature

In this paper, Mg-doped black ZnO microspheres with the characteristics of large surface area and surface oxygen vacancies were synthesized using the sol-gel method. The humidity sensing behavior of the Mg-doped ZnO for relative humidity (RH) from 11% to 95% was measured at room temperature. The superior humidity sensing performance recorded for Mg-doped ZnO microspheres (1.5 mol%) exhibits a dramatic change of impedance of about four orders of magnitude, excellent sensing linearity, small hysteresis (4.1%), a fast sensing response time of as low as 24 s, and a recovery time of 12 s. Our studies demonstrate that Mg dopant can significantly enhance the humidity sensing performance of black ZnO. This benefits from the Mg-doped ZnO (1.5 mol%) microspheres having a high level of surface adsorption and the abundant oxygen vacancies on the surface. Such a new material could be very useful to develop simple and high-performance humidity sensors for future applications in varying commercial fields and industries.

[1]  Vijay K. Tomer,et al.  One pot synthesis of mesoporous ZnO–SiO2 nanocomposite as high performance humidity sensor , 2015 .

[2]  Iulian Petrila,et al.  Reduced graphene oxide decorated with Fe doped SnO 2 nanoparticles for humidity sensor , 2017 .

[3]  Reza Darvishi Cheshmeh Soltani,et al.  Europium-doped ZnO as a visible light responsive nanocatalyst: Sonochemical synthesis, characterization and response surface modeling of photocatalytic process , 2014 .

[4]  Saliha Ilican,et al.  Sol–gel derived Li–Mg co-doped ZnO films: Preparation and characterization via XRD, XPS, FESEM , 2012 .

[5]  Akira Ohtomo,et al.  MgxZn1−xO as a II–VI widegap semiconductor alloy , 1998 .

[6]  Yan Wu,et al.  Enhanced solar light photocatalytic properties of ZnO nanocrystals by Mg-doping via polyacrylamide polymer method , 2016 .

[7]  Lu Ze,et al.  MoS2-modified ZnO quantum dots nanocomposite: Synthesis and ultrafast humidity response , 2017 .

[8]  Javed Iqbal,et al.  Influence of Mg doping level on morphology, optical, electrical properties and antibacterial activity of ZnO nanostructures , 2014 .

[9]  Tong Zhang,et al.  Study on humidity sensing properties based on composite materials of Li-doped mesoporous silica A-SBA-15 , 2008 .

[10]  Yang Li,et al.  Crosslinked and quaternized poly(4-vinylpyridine)/polypyrrole composite as a potential candidate for the detection of low humidity. , 2008, Talanta.

[11]  Xinyu Xue,et al.  Enhanced piezo-humidity sensing of Sb-doped ZnO nanowire arrays as self-powered/active humidity sensor , 2015 .

[12]  Hongyan Zhang,et al.  The enhancement of humidity sensing performance based on Eu-doped ZnO , 2019, Current Applied Physics.

[13]  Xinyu Xue,et al.  High-performance self-powered/active humidity sensing of Fe-doped ZnO nanoarray nanogenerator , 2015 .

[14]  Junhan Kong,et al.  Synthesis of Mg-doped hierarchical ZnO nanostructures via hydrothermal method and their optical properties , 2016 .

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

[16]  B. Lescop,et al.  Interplay effects of humidity and UV light sensitivities of Zn0.9Mg0.1O nanogranular thin films , 2015 .

[17]  Shui-Jinn Wang,et al.  Enhanced sensing performance of relative humidity sensors using laterally grown ZnO nanosheets , 2014 .

[18]  Ritu Srivastava,et al.  Mg-doped ZnO nanostructures for efficient Organic Light Emitting Diode , 2019, Vacuum.

[19]  S. R. Lukić-Petrović,et al.  Effect of annealing temperature on structural and optical properties of Mg-doped ZnO nanoparticles and their photocatalytic efficiency in alprazolam degradation , 2014 .

[20]  P. Tripathi,et al.  Band gap engineering and enhanced photoluminescence of Mg doped ZnO nanoparticles synthesized by wet chemical route , 2015 .

[21]  Hangxun Xu,et al.  A Highly Efficient Metal‐Free Oxygen Reduction Electrocatalyst Assembled from Carbon Nanotubes and Graphene , 2016, Advanced materials.

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

[23]  Wei Wang,et al.  Humidity sensor based on LiCl-doped ZnO electrospun nanofibers , 2009 .

[24]  Ming Chang,et al.  Rapid synthesis of ZnO dandelion-like nanostructures and their applications in humidity sensing and photocatalysis , 2014 .

[25]  Pushpa Giri,et al.  Effect of Mg doping in ZnO buffer layer on ZnO thin film devices for electronic applications , 2016 .

[26]  Weiwei Yu,et al.  Graphene oxide/WS2/Mg-doped ZnO nanocomposites for solar-light catalytic and anti-bacterial applications , 2017 .

[27]  Tong Zhang,et al.  Humidity sensing properties of KCl-doped ZnO nanofibers with super-rapid response and recovery , 2009 .

[28]  Hui Li,et al.  Effect of annealing atmosphere on the photoluminescence of ZnO nanospheres , 2009 .

[29]  Anchal Srivastava,et al.  Green photoluminescence and photoconductivity from screen-printed Mg doped ZnO films , 2018 .

[30]  Prasanta Kumar Mahapatra,et al.  Optical properties and enhanced photocatalytic activity of Mg-doped ZnO nanoparticles , 2018, Physica E: Low-dimensional Systems and Nanostructures.

[31]  Xincun Dou,et al.  2D TiO2 nanosheets for ultrasensitive humidity sensing application benefited by abundant surface oxygen vacancy defects , 2018, Sensors and Actuators B: Chemical.

[32]  Jing Zhao,et al.  Highly sensitive humidity sensor based on high surface area mesoporous LaFeO3 prepared by a nanocasting route , 2013 .

[33]  Tong Zhang,et al.  Humidity sensors based on Li-loaded nanoporous polymers , 2014 .

[34]  Jun Zhang,et al.  AuNPs Hybrid Black ZnO Nanorods Made by a Sol-Gel Method for Highly Sensitive Humidity Sensing , 2018, Sensors.

[35]  Erdal Sönmez,et al.  A study of Eu incorporated ZnO thin films: An application of Al/ZnO:Eu/p-Si heterojunction diode , 2016 .

[36]  Zhenhong Jia,et al.  Er-enhanced humidity sensing performance in black ZnO-based sensor , 2018 .

[37]  Xiaobo Chen,et al.  Increasing Solar Absorption for Photocatalysis with Black Hydrogenated Titanium Dioxide Nanocrystals , 2011, Science.

[38]  Tong Zhang,et al.  Preparation and humidity sensitive property of mesoporous ZnO–SiO2 composite , 2010 .

[39]  Shuang Wu,et al.  A facile approach for the fabrication of Au/ZnO-hollow-sphere-monolayer thin films and their photocatalytic properties , 2017 .

[40]  Huilin Hou,et al.  Fabrication of Mg-doped ZnO nanofibers with high purities and tailored band gaps , 2016 .

[41]  X Wang,et al.  X-ray photoelectron spectroscopy and auger electron spectroscopy studies of Al-doped ZnO films , 2000 .

[42]  John Bosco Balaguru Rayappan,et al.  A highly sensitive humidity sensor based on DC reactive magnetron sputtered zinc oxide thin film , 2010 .