Metal and metal oxide co-functionalized single-walled carbon nanotubes for high performance gas sensors
A method of co-functionalizing single-walled carbon nanotubes for gas sensors, which includes the steps of: fabricating single-walled carbon nanotube interconnects; synthesizing tin oxide onto the single-walled carbon nanotube interconnects; and synthesizing metal nanoparticles onto the tin oxide coated single-walled carbon nanotube interconnects.
1. A method of co-functionalizing single-walled carbon nanotube interconnects for gas sensors, the method comprising:
fabricating by alignment single-walled carbon nanotube interconnects;
synthesizing discrete tin oxide nanocrystallites onto a surface of the single-walled carbon nanotube interconnects by electrodeposition; and
synthesizing metal nanoparticles onto the discrete tin oxide nanocrystallites and the surface of the single-walled carbon nanotube interconnects by electrodeposition, and
wherein an overall sensitivity of the gas sensor is enhanced compared to other single-walled carbon nanotube gas sensors.
2. The method of claim 1 , comprising:
fabricating the single-walled carbon nanotube interconnects across a gap between a pair of electrodes.
3. The method of claim 2 , further comprising:
controlling the number of single-walled carbon nanotube interconnects by adjusting a concentration of single-walled carbon nanotube in a solution.
4. The method of claim 2 , further comprising:
controlling the number of single-walled carbon nanotube interconnects by adjusting an alignment time.
5. The method of claim 3 , wherein the aligning of the single-walled carbon nanotube interconnects comprises:
an AC dielectrophoresis process.
6. The method of claim 1 , wherein the tin oxide nanocrystallites are synthesized onto the single-walled carbon nanotube interconnects from an electrolyte solution comprised of NaNO 3 , HNO 3 , SnCl 2 .5H 2 O and/or other tin ion precursors.
7. The method of claim 1 , wherein the metal nanoparticles are palladium (Pd).
8. The method of claim 1 , wherein the metal nanoparticles are platinum (Pt).
9. The method of claim 1 , wherein the metal nanoparticles are gold (Au).
10. The method of claim 1 , further comprising:
fabricating a plurality of said co-functionalizing single-walled carbon nanotube interconnects, which form a plurality of gas sensors, and wherein the plurality of gas sensors are wire-bonded and each sensor is connected in series with a load resistor.
11. The method of claim 1 , wherein the gas sensors are co-functionalized for sensing at room temperature.
12. A method of co-functionalizing single-walled carbon nanotube interconnects for gas sensors, the method comprising:
fabricating by alignment single-walled carbon nanotube interconnects across a gap between a pair of electrodes;
templating discrete tin oxide nanocrystallites onto a surface of the single-walled carbon nanotube interconnects by electrodeposition; and
depositing metal nanoparticles onto the discrete tin oxide nanocrystallites and the surface of the single-walled carbon nanotube interconnects by electrodeposition, and
wherein an overall sensitivity of the gas sensor is enhanced compared to other single-walled carbon nanotube gas sensors.
13. The method of claim 12 , further comprising:
controlling the number of single-walled carbon nanotube interconnects by adjusting a concentration of single-walled carbon nanotube in a solution.
14. The method of claim 12 , further comprising:
controlling the number of single-walled carbon nanotube interconnects by adjusting an alignment time.
15. The method of claim 14 , wherein the aligning of the single-walled carbon nanotube interconnects comprises:
an AC dielectrophoresis process.
16. The method of claim 12 , comprising:
an electrolyte solution comprised of NaNO 3 , HNO 3 , SnCl 2 .5H 2 O and/or other tin ion precursors which is templated onto the single-walled carbon nanotube interconnects as the discrete tin oxide nanocrystallites.
17. The method of claim 12 , wherein the metal nanoparticles are palladium (Pd).
18. The method of claim 12 , wherein the metal nanoparticles are platinum (Pt).
19. The method of claim 12 , wherein the metal nanoparticles are gold (Au).
20. The method of claim 12 , further comprising:
fabricating a plurality of said co-functionalizing single-walled carbon nanotube interconnects, which form a plurality of gas sensors, and wherein the plurality of gas sensors are wire-bonded and each sensor is connected in series with a load resistor.
21. The method of claim 12 , wherein the gas sensors are co-functionalized for sensing at room temperature.