title: Electrospinning of porphyrin/polyvinyl alcohol (PVA) nanofibers and their acid vapor sensing capability.
abstract: Fluorescing 5,10,15,20-terakis(1-methyl-4-pyridinio)porphyrin tetra(p-toluenesulfonate) (TMPyP)-embedded and -coated polyvinyl alcohol (PVA) nanofibers were fabricated by using the electrospinning technique. To improve nonpolar solvent solubility of TMPyP/PVA nanofibers, tetraethyl orthosilicate (TEOS) was used as a cross-linking agent. UV-vis spectroscopy showed a strong Q band and two relatively weak Soret bands from the TMPyP/PVA nanofibers, and revealed that the TMPyP molecules were homogeneously loaded to the fibers. Scanning electron microscopy revealed that the electrospun nanofibers had ultrafine structures with an average diameter of ca. 250 nm. X-ray photoelectron spectroscopy confirmed the compositional structure of TMPyP/PVA/TEOS nanofibers and revealed the relative coverage of TMPyP molecules on the surface of TMPyP-embedded and TMPyP-coated PVA/TEOS fibers. For the comparison of the acid vapor sensitivity, TMPyP-embedded PVA/TEOS films, and TMPyP-embedded PVA/TEOS fibers, TMPyP-coated PVA/TEOS fibers were exposed to 1N nitric-acid vapor for 20-60 seconds. Fluorescence microscopy revealed that TMPyP-coated PVA/TEOS nanofibers exhibited better acid-sensing capability than TMPyP-embedded PVA/TEOS nanofibers and films.
authors: Department of Organic and Nano Engineering and Institute of Nano Science and Technology, Hanyang University, 17 Haengdang-Dong, Seongdong-Gu, Seoul 133-791, Korea.
authors: Kihun
authors: K
authors: Jang
authors: Il Woong
authors: IW
authors: Baek
authors: Sung Yul
authors: SY
authors: Back
authors: Heejoon
authors: H
authors: Ahn
mesh_terms: D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry; D005740:Gases / Q000032:analysis; D008855:Microscopy, Electron, Scanning; D008856:Microscopy, Fluorescence; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods*; D017942:Nitric Acid / Q000032:analysis*; D010316:Particle Size; D056951:Photoelectron Spectroscopy; D011142:Polyvinyl Alcohol / Q000737:chemistry*; D011166:Porphyrins / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D005456:Fluorescent Dyes; D005740:Gases; D011166:Porphyrins; C021096:tetra(4-N-methylpyridyl)porphine; D017942:Nitric Acid; D011142:Polyvinyl Alcohol