Abstracts Book - IMRC 2018

• SF2-P008
DEVELOPMENT OF CO2 SENSORS BASED ON ZnO
NANOSTRUCTURES.
Marco Polo Munguia Martín 1 , Venkata Krishna Karthik Tangirala 2 , María Isabel Reyes
Valderrama 1 , Juan Hernández Avila 1 , Demetrio Mendoza Anaya 3 , Ventura Rodriguez Lugo 1
1 Universidad Autónoma del Estado de Hidalgo, Área Académica de Ciencias de la Tierra y
Materiales, Instituto de Ciencias Básicas e Ingeniería, Mexico. 2 Universidad Autónoma del
Estado de Hidalgo, Escuela Superior de Tepeji del Rio, Universidad Autónoma del Estado de
Hidalgo, Mexico. 3 Instituto Nacional de Investigaciones Nucleares (ININ), Instituto Nacional de
Investigaciones Nucleares, Mexico.
In the present work zinc oxide (ZnO) nano structures were synthesized utilizing
homogeneous precipitation method with zinc acetate as Zn precursor and urea as
precipitation agent. All the synthesized ZnO powders were aged for 64h and
calcined at 100 °C. The effect of calcination time (5,10,13,15 and 20 h) on ZnO
structural, morphological and gas sensing properties were studied in detail. All the
powders were characterized by X-ray diffraction (XRD), scanning electron
microscopy (SEM) and in a homemade gas sensing system. X-ray analysis confirms
the formation wurtzite ZnO nanostructures with a preferential orientation (002)
with an average crystallite size ~ 20 nm. Increase in the calcination time changed
the preferential orientation (001) to (002) indicating the growth of hexagonal Zn rich
surface [1]. SEM analysis shows different morphologies of ZnO structures such as
flakes, particles, laminar sheets and hollow nuts with increase in the calcination
time, respectively. CO2 sensitivities of all samples were obtained at different CO2
concentrations (1,3,5 and 7 %) and at different sensor operation temperatures (100,
200 and 300 °C). Increase in the calcination time resulted in more porous structures
which subsequently resulted in higher CO2 sensitivities[2].
References
[1] Quanzi Yuan et al., “Ab Initio Study of ZnO-Based Gas-Sensing
Mechanisms : Surface Reconstruction and Charge Transfer Ab Initio Study
of ZnO-Based Gas-Sensing Mechanisms : Surface Reconstruction and,”
2009, 6107–13, doi:10.1021/jp810161j.
[2] Weiwei Guo et al., “Gas-Sensing Performance Enhancement in ZnO
Nanostructures by Hierarchical Morphology,” Sensors and Actuators, B:
Chemical 166–167 (2012): 492–99, doi:10.1016/j.snb.2012.02.093.
Keywords: Zinc oxide,, wurtzite, CO2
Presenting authors email: Denwok_xps15l521x@hotmail.com