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Gas Adsorption in Carbon Nanotubes. Northern Arizona University Department of Physics & Astronomy Buddy Davis Mentor: Randy Dillingham. Carbon Nanotubes. About ten nanometers thick Single walled and double walled Different structure styles. Uses. Structural Electrical
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Gas Adsorption in Carbon Nanotubes Northern Arizona University Department of Physics & Astronomy Buddy Davis Mentor: Randy Dillingham
Carbon Nanotubes • About ten nanometers thick • Single walled and double walled • Different structure styles Uses • Structural • Electrical • Gas Storage/Filter
Etching H2SO4 HNO3 Etched for one week in .01 molar sulfuric/nitric acid H2SO4 & HNO3 Etching creates defects in the nanotubes
Mass Spectroscopy • Voltages of mass spec varied to scan • Detector shows what masses are present.
X-ray Photoelectron Spectroscopy(XPS) X-rays shined on sample to eject electrons Energy of emitted electrons based on binding energy of sample atom
Nitrogen Exposure • Nanotubes placed in vacuum 5X10-9 Torr • Nitrogen gas was then introduced under a pressure of 1x10-7 Torr for 40 minutes • The vacuum was then restored to 5X10-9 Torr
XPS Data • Comparing etched and unetched reveled sulfur left from etching process.
XPS Data • Significant change in nitrogen found
Atomic Concentration Data UE E EE Nitrogen Carbon Oxygen Sulfur
Future Experiments • Testing unetched exposed tubes • Testing alternative gasses (CF4) • Alternative methods of testing such as Fourier transform infrared spectroscopy