Charge carriers, polythiophenes

Ohkita H, Cook S, Astuti Y, Duffy W, Tierney S, Zhang W, Heeney M, McCulloch I, Nelson J, Bradley DDC, Durrant JR (2008) Charge carrier formation in polythiophene/fullerene blend films studied by transient absorption spectroscopy. J Am Chem Soc 130 3030... 

Photoelectrochemical cells with polythiophene film as an active electrode and a lead plate as a counter electrode in Pb (C104) acetonitrile electrolyte has an open circuit voltage of 0.8 V, short circuit current of 2 x 10 4 A cm-2, efficiency coefficient of 0.03%, fill factor of 15% [194]. The absorption and photosensitivity spectra of such a cell are shown in Fig. 24. The small bathochromic shift in the longwave region for photosensitivity may be related to the photogeneration of the charge carriers via surface states. The photosensitivity maximum is close to the maximum solar intensity. The parameters exceed the ones obtained with polyacetylene. 

Heterojunctions of polythiophene with polypyrrole [195] and Cds [196] of the Schottky type were constructed and tested. The height of the barrier was 0.8 eV. The photogeneration of the charge carrier takes place in the depletion layer of the thiophene with consequent separation in the barrier electric field. 

Stable polythiophene semiconductors 237 incorporating the thieno[2,3-fc]thiophene ring system were synthesized by Stille coupling of 5,5 -dibromo-4,4 -dialkyl-2,2 -bithiophene 235 with thieno[2,3-fc]thiophene-2,5-diylbis(trimethystannane) 236 (Scheme 48). The polymers 237 described showed both good charge carrier mobility and stability to ambient air and light [62],... 

Savenije, T.J. et ah. The effect of thermal treatment on the morphology and charge carrier dynamics in a polythiophene-fullerene bulk heterojunction, Adv. Fund. Mater. 15, 1260-1266, 2005. 

Figure 13.4 Charge generation in PCBMipolyhtiophene solar cells. Charge-transfer state generation, separation, and recombination rates for P3HT PCBM are shown. (Reprinted with permission from Journal of the American Chemical Society, Charge Carrier Formation in Polythiophene/ Fullerene Blend Films Studied by Transient Absorption Spectroscopy by H. Ohkita, S. Cook, Y. Astuti etal., 130, 10,3030-3042. Copyright (2008) American Chemical Society)...

H. Ohkita, S. Cook, Y. Astuti, W. Duffy, S. Tierney, W. Zhang, M. Heeney, I. McCulloch, J. Nelson, D.D.C. Bradley, and J.R. Durrant, Charge carrier formation in polythiophene/ fullerene blend films studied by transient absorption spectroscopy, J. Am. Chem. Soc., 130, 3030-3042 (2008). 

A. Saeki, S. Seki, T. Sunagawa, K. Ushida, S. Tagawa, Charge-carrier dynamics in polythiophene films studied by in situ measurement of flash-photolysis time-resolved microwave conductivity (FP-TRMC) and transient optical spectroscopy (TOS). Philos. Mag. 86, 1261-1276 (2006)... 

Elarima, Y, Y. Kunugi, K. Yamashita, and M. Shiotani. 2000. Determination of mobilities of charge carriers in electrochemically anion-doped polythiophene film. Chem Phys Lett 317 310. 

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