Vol.:(0123456789) 1 3
J Mater Sci: Mater Electron
DOI 10.1007/s10854-017-8042-8
Zeolite A coated Zn
1−X
Cu
X
O MOS sensors for NO gas detection
Sezin Galioglu
1
· Irmak Karaduman
2
· Tuğba Çorlu
2
· Burcu Akata
1,3
·
Memet Ali Yıldırım
4
· Aytunç Ateş
5
· Selim Acar
1
Received: 20 September 2017 / Accepted: 11 October 2017
© Springer Science+Business Media, LLC 2017
growth method. zeolite A coated Zn
0.75
Cu
0.25
O sensor exhib-
ited both high selectivity and high response towards NO
gas. The detection limit of the zeolite coated Zn
0.75
Cu
0.25
O
sensor was shifted to 20 ppb for NO gas at operating tem-
perature of 25 °C.
1 Introduction
Recently, semiconducting metal oxide (MOS) gas sensors
have attracted considerable attention because of their many
advantages over traditional chemical analysis methods;
these advantages include fast response, high sensitivity,
small dimensions, ease of use, portability, simple design,
simplicity of fabrication, real-time detection, low detection
limits, low cost, and low power consumption [1, 2]. Among
them, ZnO is the technologically important semiconducting
material used as a sensing material due to its low cost, long-
life, thermal and chemical stability and simple fabrication
process [2].
Successful development of ZnO based gas sensors for
commercialization requires achieving three “S”: sensitiv-
ity, selectivity, and stability [3]. Among them, stability is
considered as the most important requirement for commer-
cial devices with other properties remaining acceptable.
Sensitivity is usually improved by doping noble catalyst
particles and annealing processes. It is closely related to
the detection limit of the sensor, which at present is as
low as several ppm for the commercially gas sensor. Li
et al. demonstrated that Ce-doping was increased sensing
properties of ZnO microspheres sensors which operated at
low temperature [4]. They reported that the Ce doped ZnO
microspheres exhibited the highest sensitivity with rapid
response and recovery times compared to pure one [4].
Hjiri et al. reported the Al-doped ZnO sensorexhibiting
Abstract In the current study, a novel and highly sen-
sitive gas sensing material for the detection of NO gas
was reported. Copper doped zinc oxide nanostructures
(Zn
1−x
Cu
x
O, where x = 0.25 steps) were grown as a semi-
conducting sensor material by using Successive Ionic Layer
Adsorption and Reaction (SILAR) method. The structural,
morphological and optical properties of nanostructures
were investigated by X-Ray Difractometer (XRD), Scan-
ning Electron Microscope (SEM) and UV–visible spectrom-
eter. NO gas sensing measurements were carried out as a
function of temperature and gas concentrations. The sen-
sors exhibited acceptable responses towards 50 ppb NO gas
at operating temperature of 55 °C. The sensors were opti-
mized and the maximum response of 8% was obtained for
the Zn
0.75
Cu
0.25
O sensor. To increase sensor selectivity, zeo-
lite A (LTA) microporous flm, used as a flter, was coated
on the optimized Zn
0.75
Cu
0.25
O sensor by using secondary
Electronic supplementary material The online version of this
article (doi:10.1007/s10854-017-8042-8) contains supplementary
material, which is available to authorized users.
* Irmak Karaduman
irmak.karaduman06@gmail.com
1
Department of Micro and Nanotechnology, Middle East
Technical University, Ankara, Turkey
2
Department of Physics, Science Faculty, Gazi University,
Ankara, Turkey
3
Central Laboratory, Middle East Technical University,
Ankara, Turkey
4
Department of Electric Electronics Engineering, Engineering
Faculty, Erzincan University, Erzincan, Turkey
5
Department of Material Engineering, Engineering
and Natural Sciences Faculty, Yıldırım Beyazıt University,
Ankara, Turkey