Air pollutants like NO2 are harmful in small concentrations, and gas sensors are needed that can detect gases in such low quantities. A promising candidate for this is doping graphene, a single layer of carbon atoms, with nitrogen impurities, and using this material as a chemores
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Air pollutants like NO2 are harmful in small concentrations, and gas sensors are needed that can detect gases in such low quantities. A promising candidate for this is doping graphene, a single layer of carbon atoms, with nitrogen impurities, and using this material as a chemoresistor. This thesis investigates the fabrication and characterization of this nitrogen-doped graphene (NDG) in a low-pressure chemical vapor deposition (LPCVD) process. This is first tested with a mixture of methane and ammonia gas as carbon and nitrogen precursors respectively. After this is proven to be ineffective, a benzene-like liquid called pyridine is bubbled into the reactor to supply both the carbon and nitrogen, and grow graphene on both copper and molybdenum catalysts. The graphene is characterized by Raman spectroscopy, SEM, FTIR, EDX and XPS measurements. The CVD parameters are changed to optimize the quality of the grown graphene. The nitrogen doping couldn't be confirmed, but a CVD recipe is now available to grow graphene with pyridine, manufacture a gas sensor with this new material and conduct NO2 gas tests to measure the sensor's sensitivity.