Gas Sensitivity of Poly (3, 4-ethylene dioxythiophene) Prepared by a Modified LB Film Method

An arachidic acid/poly （3, 4-ethylene dioxythiophene） （AA/PEDOT） multilayer Langmuir-Blodgett （LB） film was prepared by a modified LB film method. The theories were utilized to explain the effects between HCl molecule and LB film. The gas sensitivity mechanism of poly （3, 4-ethylene dioxythiophene） （PEDOT） multilayer film can be explained by the charge transfer between p system of PEDOT and oxidization HCl system. The gas sensitivity of PEDOT LB film deposited interdigital electrode to HCl was tested. The results showed that film thickness, treating temperature, deposition speed had different influence on film gas sensitivity. The AA/PEDOT film deposited device exhibited nonlinear behavior to HCl gas at lower concentration （20-60 ppm） and linear response behavior at higher gas concentration was observed. The time of the compound LB film of the AA/PEDOT responding to the 30 ppm HCl gas is about 20 seconds, which is far quicker than the time of the film to the PEDOTPRESS film（about 80 seconds）. It is not higher film press to better film. When the film press attains 45 mNs/m, the sensitivity of the AA/PEDOT film on the contrary descends.

Synthesis, Crystal Structure, and Photoluminescent Property of a 2-Fold Interpenetrating Znic(Ⅱ) Coordination Polymer with 2,5-Dicarboxylic Acid-3,4-ethylene Dioxythiophene

A three-dimensional coordination polymer,[Zn2(L)2(bpp)(H2O)2]n(H2L=2,5-dicarboxylic acid-3,4-ethylene dioxythiophene,bpp=1,3-di(4-pyridyl)propane),was synthesized with high yield under solvothermal reaction conditions and structurally characterized by elemental analysis,infrared spectra,thermogravimetric analysis,powder X-ray diffraction and single-crystal X-ray diffraction analysis.It crystallizes in orthorhombic space group Pnma with a=16.6542(9),b=18.0868(10),c=10.7528(5)?,V=3239.0(3)?3,Z=4,Dc=1.684 g/cm3,Mr=821.38,Dc=1.684 g/cm3,μ=1.683 mm-1,F(000)=1672,R=0.0466,wR=0.0933 and S=1.066.The compound exhibits a three-dimensional structure,which can be simplified into a 2-fold interpenetrated pcu topological network.Moreover,it displays luminescence emission in the solid state at room temperature.