KAJIAN PENGARUH KONSENTRASI UREA DALAM SIFAT OPTIK NANOFIBER GRAPHENE OXIDE/ PVA (POLYVINYL ALCOHOL) YANG DIFABRIKASI MENGGUNAKAN TEKNIK ELECTROSPINNING; STUDY OF EFFECT UREA ON OPTICAL PROPERTIES OF GRAPHENE OXIDE/POLYVINYL ALCOHOL NANOFIBERS FABRICATED BY ELECTROSPINNING TECHNIQUE

Efelina, Vita, Imam Santoso

2015 | Disertasi | FMIPA

We report how the effect of urea on optical properties graphene oxide/polyvinil alcohol (PVA) nanofibers fabricated by electrospinning technique. Graphene oxide has been prepared by oxidizing purified natural flake graphite via modified Hummers method and has been graphene oxide nanofiber doped by urea has been fabricated by using electrospinning technique with polyvinyl alcohol (PVA) as matrix of nanofibers. The samples were characterized by Scanning Electron Microscopy (SEM), Raman spectra, Fourier Transform Infrared and UV-Vis spectra for optical properties analysis. Complex optical constant such as refractive index, dielectric constant and optical conductivity are calculated from absorbance spectra are extracted using by Kramers-Kronig method. The urea doped graphene oxide nanofiber exhibited an n-type behavior. The result showed that urea doped graphene oxide nanofiber can be successfully synthesized. It was observed absorption width peak at 2.9 eV. SEM measurements show uniform hollow graphene oxide/PVA fibers formation and diameter size approximately 239± 32 nm. While graphene oxide/PVA doped urea diameter size be increased approximately 273± 31 nm. The result of UV-Vis spectroscopy showed that the greater urea for refractive index (n) and extinction coefficient (k) have a tendency to decrease the values n and k with increases of the dopant urea, so it?s potentially as a transparent and conductive electrode

Kata Kunci : graphene oxide doping urea nanofiber;electrospinning; optical properties; kramers-kronig