1. HIGH SENSITIVITY SENSORS
Individual project
Nanomaterials
HIGH SENSITIVITY SENSORS
Teacher:
Cristina Felea
Student:
Cenan Marius Paul

2. INTRODUCTION
Oxford English Dictionary defines the sensor as “a device that detects and records the conditions or properties, indicate or sometimes respond to information received”

3. Features: use area resolution (sensitivity)
maximum stimulus frequency that can be detected (selectivity)
accuracy (measurement error)
sensor size and weight
operating temperature and environmental conditions
life
long-term stability and cost

4. Use to measurement of: pressure distance movements speed acceleration
force
temperature
chemical concentration

5. The sensor sensitivity can be improved by doping (changing the concentration) or
by microstructural changes such as reducing the particle size to nanodimensions (5-50 nm), which improves the properties and performance of gas sensors due to increased surface area.
OXIDE SEMICONDUCTOR FILMS USED AS GAS SENSORS FOR ENVIRONMENTAL MONITORING

6. Conductive films used as gas sensors
Conductive materials used as gas sensors
Material
Working temperature
(ºC)
TiO2
SrTiO3
Ga2O3
Nb2O3
CeO2
BaFeNb9O10
720
BaTi2Nb4O25
BaFe0.8Hf0.2O3
Material
Working temperature
(ºC)
SnO2
ZnO
TiO2
CeO2
Nb2O5
400
WO3
500
Ga2O3

7. Sensors based on oxide materials (SMO)
report, evaluate and monitor the presence of gas
chemical resistance and high temperature field that can be used

8. Network image of Tungsten oxide nanowires

9. PRELIMINARY RESULTS We investigated the behavior of several oxides and
TiO2 has been the most extensively used in controlling air/fuel ratio in internal combustion engines. This oxide can also be used in wastewater purification.

10. NANODOCTORS IN 30 YEARS to provide medication tumor removers
analysis and rebuild tissue destroyed by accident
A nanorobot, able to administer poison only target bacteria, would greatly simplify things, “said Ottilie Saxl, chief executive of the U.S. Institute for Nanotechnology”.

11. REFERENCES: www.jnanobiotechnology.com/articles www.chimie.go.ro
P. Tmoseley, J. O. W.Norris, D. E. Williams, Techniques and mechanisms in gas sensing, Adam Hilger, Bristol, 1991
. E. Williams, P. T. Moseley, J. Mater. Chem., 1, (1991)
M. Kuwabara, T. Ide, Co gas sensivity in porous semiconducting barium titanate, Am. Ceramic Soc. Bull., 66, (1987)
C. M. Chiu, Y. U. Chang, The structure, electrical and sensing properties for CO of the La0.8Sr0.2CO1-xNixO3- system, Mater. Sci. Eng. A, 266, 93-98(1999)

12. Thank you!