High Fluorescence Properties Of Laser Etching PPV

The design and fabrication of fluorescence chemical sensors had attracted more and more interests of researchers for their widely practical and potential applications. Some special fluorescent chemical sensor could be used to detect TNT, DNT and other explosive agent which is very important for military wars, industrial production, daily life safety and so on. Poly(p-phenylenevinylene)(PPV)and its derivative, which have large quantity of the conjugatedπstructures, are very easy to produce fluorescence after being excited.Vertical pulse laser was used to prepare higher fluorescence modified PPV film at ambient temperature and atmospheric pressure. The Laser-induced forward transfer(LIFT)technique had been used to produce nano-PPV film. The morphology, structure and chemical composition of the films were characterized by the SEM, FTIR, XPS and PL spectra. SEM analysis showed that the surface of the modified PPV film by the VPLD was roughness and there was no damage under certain condition; SME images of the nano-PPV film by the LIFT presented nano-network structure and the diameter of the nanowire from approximately 25nm to 30nm. FTIR,XPS spectra showed that the composition of the modified PPV film by the laser etching had changed and the conjugated structure of the film had been increased, the fluorescence spectra had been happened the red shift. The PL spectra of nano-PPV film which was prepared by the LIFT had been happened blue shift because of the quantum size effect of nanostructure. The two kinds of PPV films contacted with the TNP, TNT respond to the quenching experiment, respectively. We found that the two kinds of films all had been quenched much more than the plain film and the extent of the quenching even much bigger than the unmodified PPV film within the shorter time.