(Photo)conductivity of conjugated oligomer films: mobile charge carrier formation by oxygen

被引:15
作者
Luer, L [1 ]
Egelhaaf, HJ [1 ]
Oelkrug, D [1 ]
机构
[1] Univ Tubingen, Inst Phys Chem, D-72076 Tubingen, Germany
关键词
conductivity; doping; oligomer films; luminescence quenching;
D O I
10.1016/S0925-3467(97)00131-6
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Electrical dark and photo conductivities, sigma(d) and sigma(p), of vapor deposited films of alpha-sexithiophene, 4,4'-distyrylstilbene, and titaniumoxophthalocyanine were investigated as function of temperature, exposure time to oxygen of variable pressure, irradiation time and intensity. Molecular oxygen increases sigma(d) and sigma(p) by orders of magnitude. Cartful removal of elevated temperatures under high vacuum and assistance of irradiation will reduce both sigma(d) and sigma(p) to almost negligible values. From the rise and decay kinetics of conductivity and from luminescence quenching it is concluded that oxygen must be complexed with the film constituting molecules in order to act as separation center for electrical charge. The complex is formed already in the dark, but more efficiently upon irradiation. The interaction with oxygen is essentially reversible but leads in a side reaction also to irreversibly oxidized photoproducts. (C) 1998 Elsevier Science B.V.
引用
收藏
页码:454 / 460
页数:7
相关论文
共 21 条
[1]   REVERSIBLE CHARGE-TRANSFER COMPLEXES BETWEEN MOLECULAR-OXYGEN AND POLY(3-ALKYLTHIOPHENE)S [J].
ABDOU, MSA ;
ORFINO, FP ;
XIE, ZW ;
DEEN, MJ ;
HOLDCROFT, S .
ADVANCED MATERIALS, 1994, 6 (11) :838-841
[2]   CHEMICAL TUNING OF ELECTROLUMINESCENT COPOLYMERS TO IMPROVE EMISSION EFFICIENCIES AND ALLOW PATTERNING [J].
BURN, PL ;
HOLMES, AB ;
KRAFT, A ;
BRADLEY, DDC ;
BROWN, AR ;
FRIEND, RH ;
GYMER, RW .
NATURE, 1992, 356 (6364) :47-49
[3]   Influence of oxygen doping on the photoconductivity of pi-conjugated molecules [J].
Egelhaaf, HJ ;
Luer, L ;
Oelkrug, D ;
Winter, G ;
Haisch, P ;
Hanack, M .
SYNTHETIC METALS, 1997, 84 (1-3) :897-898
[4]   Characterization of oriented oligo(phenylenevinylene) films and nano-aggregates by UV/Vis-absorption and fluorescence spectroscopy [J].
Egelhaaf, HJ ;
Gierschner, J ;
Oelkrug, D .
SYNTHETIC METALS, 1996, 83 (03) :221-226
[5]   AN ALL-ORGANIC SOFT THIN-FILM TRANSISTOR WITH VERY HIGH CARRIER MOBILITY [J].
GARNIER, F ;
HOROWITZ, G ;
PENG, XH ;
FICHOU, D .
ADVANCED MATERIALS, 1990, 2 (12) :592-594
[6]   BAND STRUCTURES OF ORGANIC THIN-FILM-TRANSISTOR MATERIALS [J].
HADDON, RC ;
SIEGRIST, T ;
FLEMING, RM ;
BRIDENBAUGH, PM ;
LAUDISE, RA .
JOURNAL OF MATERIALS CHEMISTRY, 1995, 5 (10) :1719-1724
[7]   Soluble alkyl- and alkoxy-substituted titaniumoxo phthalocyanines: Synthesis and photoconductivity [J].
Haisch, P ;
Winter, G ;
Hanack, M ;
Luer, L ;
Egelhaaf, HJ ;
Oelkrug, D .
ADVANCED MATERIALS, 1997, 9 (04) :316-+
[8]   Analysis of the photocurrent action spectra of MEH-PPV polymer photodiodes [J].
Harrison, MG ;
Gruner, J ;
Spencer, GCW .
PHYSICAL REVIEW B, 1997, 55 (12) :7831-7849
[9]   CARRIER INJECTION INTO SEMICONDUCTING POLYMERS - FOWLER-NORDHEIM FIELD-EMISSION TUNNELING [J].
HEEGER, AJ ;
PARKER, ID ;
YANG, Y .
SYNTHETIC METALS, 1994, 67 (1-3) :23-29
[10]   THE OLIGOTHIOPHENE-BASED FIELD-EFFECT TRANSISTOR - HOW IT WORKS AND HOW TO IMPROVE IT [J].
HOROWITZ, G ;
PENG, XZ ;
FICHOU, D ;
GARNIER, F .
JOURNAL OF APPLIED PHYSICS, 1990, 67 (01) :528-532