In the presence of p-toluene sulfonic acid (TSA) as a dopant, polyaniline (PAni) nanofibers, (about 80^-65 nm in diameter) were successfully synthesized with a chemical template-free method. It was found that the form...In the presence of p-toluene sulfonic acid (TSA) as a dopant, polyaniline (PAni) nanofibers, (about 80^-65 nm in diameter) were successfully synthesized with a chemical template-free method. It was found that the formation probability, morphology, and diameter of the resulting PAni-TSA nanofibers were sensitive to the synthetic conditions, such as reaction temperature, the molar ratio of TSA to aniline, and the concentration of TSA in the polymerization media. The molecular structure was characterized by using the FT-IR, Raman spectra and X-ray diffraction, which shows that the main chain structure of PAni-TSA nanofibers was in agreement with that of granular PAni.展开更多
Fluorescein/polyvinyl pyrrolidone （PVP） composite nanofibers with different fluorescein loadings （with a weight concentration of 0-5.0%） are fabricated via electrospinning. Morphologies, structures and photolumine...Fluorescein/polyvinyl pyrrolidone （PVP） composite nanofibers with different fluorescein loadings （with a weight concentration of 0-5.0%） are fabricated via electrospinning. Morphologies, structures and photoluminescent （PL） prop- erties of these straight, helical or wavelike fibers are characterized by scanning electron microscopy （SEM）, fluorescence microscopy and a spectrophotometer. It is found that the maximum emission of the as-spun fluorescein/PVP fibers occurs at 510 nm. The PL intensity of the composite fiber increases with fluorescein concentration, then fluorescence quenching appears when the concentration reaches 1.67%. The mechanism of fluorescence quenching of fiuorescein is discussed. In addition, the composite fibers exhibit a much stronger PL intensity than fluorescein/PVP bulk film owing to larger specific surface area, which makes them promising materials for biomedical applications such as probes and sensors.展开更多
文摘In the presence of p-toluene sulfonic acid (TSA) as a dopant, polyaniline (PAni) nanofibers, (about 80^-65 nm in diameter) were successfully synthesized with a chemical template-free method. It was found that the formation probability, morphology, and diameter of the resulting PAni-TSA nanofibers were sensitive to the synthetic conditions, such as reaction temperature, the molar ratio of TSA to aniline, and the concentration of TSA in the polymerization media. The molecular structure was characterized by using the FT-IR, Raman spectra and X-ray diffraction, which shows that the main chain structure of PAni-TSA nanofibers was in agreement with that of granular PAni.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.11074138,11004114,60906054, and50825206)the Shandong Provincial Natural Science Foundation for Distinguished Young Scholars,China (Grant No. JQ201103)+2 种基金the Taishan Scholars Program of Shandong Province, Chinathe National Basic Research Program of China (Grant No. 2012CB722705)the National High Technology Research and Development Program of China (Grant No. 2011AA100706)
文摘Fluorescein/polyvinyl pyrrolidone （PVP） composite nanofibers with different fluorescein loadings （with a weight concentration of 0-5.0%） are fabricated via electrospinning. Morphologies, structures and photoluminescent （PL） prop- erties of these straight, helical or wavelike fibers are characterized by scanning electron microscopy （SEM）, fluorescence microscopy and a spectrophotometer. It is found that the maximum emission of the as-spun fluorescein/PVP fibers occurs at 510 nm. The PL intensity of the composite fiber increases with fluorescein concentration, then fluorescence quenching appears when the concentration reaches 1.67%. The mechanism of fluorescence quenching of fiuorescein is discussed. In addition, the composite fibers exhibit a much stronger PL intensity than fluorescein/PVP bulk film owing to larger specific surface area, which makes them promising materials for biomedical applications such as probes and sensors.
