POSITRON ANNIHILATION AND CONDUCTIVITY MEASUREMENTS ON POLYANILINE

POSITRON ANNIHILATION AND CONDUCTIVITY MEASUREMENTS ON POLYANILINE 1 first-author 1 1 1 2 2 Department of Physics, Wuhan University, Wuhan 430072, China Department of Physics, Wuhan University, Wuhan 430072, China Department of Chemistry, Huazhong University of Science and Technology, Wuhan 430074, China Department of Chemistry, Huazhong University of Science and Technology, Wuhan 430074, China The positron lifetime spectra and electrical conductivities have been measured for polyaniline as a function of protonation level ([H + ] from 10 -7 —10 0.8 mol/L). We observed that (1) the short lifetime τ 1 , which was related to electron density in bulk, decreased with the protonation level; (2) the intermediate lifetime τ 2 ≈360ps, almost remaining constant, whereas its intensity I 2 increased with increasing protonation level which was related to the conductivity of material. These results are discussed in terms of conducting island model. Positron annihilation Polyaniline Conductivity REFERENCES Chiang J C , MacDiarmid A G . Synth Met , 1986 ; 13 : 193 Synth Met MacDiarmid A G , Chiang J C . Mol Cryst Liq Cryst , 1985 ; 121 ; 173 Mol Cryst Liq Cryst Choi H Y , Mele E J . Phys Rev Lett , 1987 ; 59 : 2188 Phys Rev Lett Levay B , Lalovic M , Ache H J . J Chem Phys , 1989 ; 90 : 3282 J Chem Phys Kobayashi Y , Zheng W , Meyer E F et al . Macromolecules , 1988 ; 22 : 2302 Macromolecules MacDiarmid A G , Chiang J C , Richter A F et al . Conducting Polymer, Special Applications. Proceedings of the workshop held at Sintra, 1986. Reidel, Dordrecht , 1987 , p 105 Ginder J M , Richter A F , MacDiarmid A G . Solid State Communications , 1987 ; 63 : 97 Solid State Communications Pouget J P , Jozefowicz M E , Epstein A J . Macromolecules , 1991 : 24 : 279 Macromolecules Epstin A J , MacDiarmid A G . Mol Cryst Liq Cryst , 1988 ; 160 : 165 Mol Cryst Liq Cryst * The Project Supported by National Natural Science Foundation of China 1993-08-25 1994-02-01 2021-02-05 1994 Nuclear Science and Techniques 01 05