الفهرس 
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Abstract
All the previous studies have been reviewed only the synthesis of graphene by microwave plasma chemical vapor deposition technique, but no study has been reviewed the synthesis of graphene oxide by (MWPCVD) technique. In this thesis, a simple experiment was constructed for rapid synthesize of graphene and graphene oxide (GO) sheets simultaneously using microwave plasma chemical vapor deposition (MWPCVD) technique, which uses a microwave source (magnetron) operating at a frequency of 2.45 GHZ and a power of 700W to produce plasma inside a tube of quartz. The high-density polyethylene which consists of small beads was used as a carbon source. The graphene and graphene oxide were deposited after the quartz tube was evacuated by a rotary pump for 30 min and exposed to microwave irradiation with a power of 700W for 2 minutes. The graphene and graphene oxide sheets were characterized by different techniques such as Transmission electron microscopy (TEM), X-ray diffraction, Raman spectroscopy, UV-Visible spectroscopy, Spectrofluorometer and FT-IR spectroscopy. TEM showed that the morphology of graphene suspension sheets are not perfectly flat but exhibit crumpled and folded. X-ray diffraction for graphene showed that the presence of a high and small peak around 2θ= 24.56ο and 2θ= 43.65ο respectively, which indicated that graphene has an amorphous carbon structure. Raman spectra indicated the difference between position and shape of peaks, crystal size and intensity ratio of the D to G modes (ID/IG) for graphene and graphene oxide. Also, the FT-IR of GO exhibits the presence of C=O (1735cm-1), O-H (3425cm-1), C=C (1625cm-1) and C-O (1078cm-1), which are revealed that graphene has been oxidized. Emission spectra of GO exhibit a broad emission band between 400 to 800 nm and from UV-Vis absorption spectrum observed that the absorption peak of GO at 235 nm. All the characteristic techniques approved that MWPCVD is appropriate for the synthesis of graphene and graphene oxide and showed the difference between them. The MWPCVD technique creates a new way to the synthesis of graphene and graphene oxide simultaneously in a short time and safe for the environment. The graphene oxide is a non-conductive material and one of the techniques to convert it to conductive material is using the laser beam to remove oxygen groups from its surface. The graphene oxide films were irradiated by (808 nm, 6W) Diode Laser for a different irradiation time (1, 1.5, 2, 2.5, and 3 min) to reduce it. The reduced graphene oxide films were characterized by different techniques to study the changes of thin films surfaces. The Raman spectrum of reduced graphene oxide showed a slight increase in ID/IG ratio, variation in the position of G and D bands to lower wave number and decrease in the average size of the sp2 clusters as compared to that in the GO spectrum. After the reduction of GO Film for 3 minutes, the UV-Vis absorption spectrum showed that the maximum absorption red shift to 270 nm. PL emission spectrum showed that the maximum of PL peaks are gradually blue shifted and FT-IR indicating that GO has been reduced. All characterization techniques showed that the reduction of GO by diode laser is successful, fast and is a non-toxic method.