ammonia gas sensor using tapered optical fiber … · ammonia gas sensor using tapered optical...
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AMMONIA GAS SENSOR USING TAPERED OPTICAL FIBER COATED WITH ZINC OXIDE NANOSTRUCTURES
NEED Ammonia is widely used gas with a strong smell and high toxicity. The inhalation of this gas is deadly. Many fatal accidents are reported annually due to the ammonia leakages.
COMPETITOR TECHNOLOGY Localised electrical sensor; Prone to EMI; Poor selectivity; High operating temperature (100 - 300°C); Limited environment.
Project Leader : Dr. Mohd Hanif Yaacob Co-Researchers : Dr. Arafat Shabaneh, Ahmed Lateef Khalaf, Dr. Zuraidah Zan, Dr. Suriati Paiman, Prof. Dr. Mohd Adzir Mahd Faculty : WiPNet, Faculty of Engineering, Universiti Putra Malaysia (UPM) Email : [email protected] Phone : +603-89466454 Expertise : Optical Nanomaterials, Sensors and Communications
WWW.SCIENCEPARK.UPM.EDU.MY
PERTANIAN • INOVASI • KEHIDUPAN
Light source
Ammonia gas molecules
Light detector/ spectrophotometer
Optical coupler
3 km optical fiber
2 X 1
INVENTION Remote ammonia optical sensor
PROTOTYPE Tapered optical fiber
coated with zinc oxide nanostructures
Zinc oxide nanoflower structures
PRINCIPLE Combining light and nanotechnology, ammonia (NH3) sensor was developed by integrating tapered (‘modified’) optical fiber with zinc oxide (ZnO) nanostructures as the gas sensing layer.
High surface area of ZnO nanostructures improves molecules interaction. Very fast response (60 s) and recovery (70 s) achieved at low temperature for remote optical fiber cable (3 km).
Tapered optical fiber
Zinc oxide coated optical fiber tip
Normal optical fiber
Visible light transmits in 1
Tapered optical fiber enhances light interaction 2
Visible light reflects out 4
20 40 60 80 100 120
0
10
20
30
40
50
Time (min)
Norm
alise
d Re
flect
ance
(%)
0.5%
1%
0.5%0.75%
0.25% 0.25%
Recovery
AirResponse Ammonia
AMMONIA OPTICAL SENSOR RESPONSE
Tapered optical fiber sensor changes its intensity (reflectance) proportionally when exposed to different ammonia concentrations.
ADVANTAGES & STRENGTHS Lightweight; Immune to electromagnetic interference (EMI); Suitable for volatile & flammable environment; Suitable for remote monitoring system (approx. 3 km); Room temperature operation; Energy saving; Competitive cost; High sensitivity and selectivity; Fast response and recovery (<one minute).
MARKET POTENTIAL Remote environmental monitoring; Oil and gas; Chemical process and logistic; Agriculture and fertilizer; Pharma- ceuticals and cleaning industries. Source: SEC 2016
0
50,000
100,000
150,000
200,000
250,000
300,000
2009 2010 2011 2012 2013 2014 2015
Ammonia World Production (in metric tons)
*2016 Ammonia market price is typically USD300/ton
PATENT NO. PI 2016700567
3 Ammonia gas molecules interact with ZnO nanostructured sensing layer & change its optical properties
500 550 600 650 700 750 800-30
-20
-10
0
10
20
30
40
50
60
70
Wavelength (nm)
Nor
mal
ised
Ref
lect
ance
(%)
Air0.25%0.5%0.75%1%
Wavelength ShiftWavelength change
Source: Häggström, Mikael (2014)