Gold Nanoparticle Chemosensors for Microscale Gas Chromatography System

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Gold Nanoparticle Chemosensors for Microscale Gas
Chromatography System
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Definitions

• Gas Chromatography
• Chemosensors
• Nanoparticles

Some pictures from http//en.wikipedia.org/wiki/G
as_chromatography
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Sensor Design

• Interdigitated Gold Electrodes on SiO2
• .3 µm electrode spacing
• 50 x 60 µm2 area
• 50 µm device spacing
• E-Beam Lithography
• Spray, Drop, or Jet

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Relevant Physical Effects

• Current is strongly dependent on barrier width
• Chemistry exploits this

• C 10-18 F
• Ec e2/2C 80 meV
• kT 26 meV

• Tunneling Current

• Coulomb Blockade

Image Source http//vonbiber.iet.unipi.it/MCdottu
torial/node2.html
Image Source http//www.shef.ac.uk/htsl/stm.htm
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Electrical Characterization

• Resistance
• Capacitance
• Parasitic
• Crosstalk
• I-V Curves
• Nonlinearity

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Noise Measurements

• White Noise
• Johnson Noise
• Interference Noise
• 60 Hz
• 1/f Noise
• Geometry Dependent

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Activation Energy

• R e-E/kT
• E .7Ec
• Crystal Structure
• K 7

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Monolayers

• Drop-dry method (Jaeger group, U. Chicago)
• Coffee Stains
• Noise Properties
• Stability

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Acknowledgements

• Kurdak Lab, Dept. Physics
• Cagliyan Kurdak, Elizabeth Covington
• Zellers Lab, Dept. EHS, SPH
• Mike Rowe, Lauren Goodrich
• Funding Sources
• TSA, WIMS