Description
(Text)
Triethylamine catalyst was used to increase themolecular weight of poly(amic acid). Inelectrospinning, diameter of PAA nanofibers wascontrolled by molecular weight of poly(amic acid) andconcentration of poly(amic acid)/N-Ndimethylformamide solution. The diameters ofpolyimide based carbon nanofibers reached to aminimum value of around 100 nm. The conductivity ofthe carbon nanofiber papers increased with thedecreasing of fiber diameters, while the mechanicalstrength of polyimide and carbon nanofiber paper wasdiameter independent. Further more, Pt wassuccessfully impregnated in carbon nanofiber.Reduction accompanied with carbonization in Ar gas atup to 1000 degree C produced small and well-dispersedPt nanoparticles (3-5 nm). Carbon dioxide treatmentexhibited the effective ability of removal ofcarbonaceous overlayers to promise a potentialenhancement Pt catalyst activity. The reduction rateof Pt ion is different at heating rate of 2 and 5degree C/min. Thus, the heating rate and timeat hightemperature strongly affected Pt nanoparticle size.
(Author portrait)
Thi Xuyen Nguyen Ms. Nguyen Thi Xuyen, completed her Master degree of NanoScienceand NanoTechnology in 2007, and is currently PhD student in thegroup of Prof. Young Hee Lee, Sungkyunkwan University, Republicof Korea. Her research interests are composite of carbonnanotubes, carbon nanofibers, electrochemistry, catalyst and fuelcell.
