The Effect of Annealing on the Charge-Carrier Dynamics in a Polymer/Polymer Bulk Heterojunction for Photovoltaic Applications
| Autor: | Tom J. Savenije, Pieter A. C. Quist, Sjoerd Veenstra, Marc M. Koetse, Laurens D. A. Siebbeles, JM Kroon |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Materials science
business.industry Annealing (metallurgy) Exciton Photoconductivity Electron Condensed Matter Physics Polymer solar cell Electronic Optical and Magnetic Materials Biomaterials Photoexcitation Chemical physics Electrochemistry Optoelectronics Charge carrier business Order of magnitude |
| Zdroj: | Advanced Functional Materials. 15:469-474 |
| ISSN: | 1616-3028 1616-301X |
| Popis: | The effect of annealing blends of poly(2-methoxy-5-(3′,7′-dimethyloctyloxy)-1,4-phenylenevinylene) (MDMO-PPV) and a poly(cyanoether phenylenevinylene) (PCNEPV) on the photoconductivity is studied. Charge carriers are generated by pulsed-laser excitation and their mobility and decay kinetics are monitored using time-resolved microwave conductivity (TRMC) measurements. Photoexcitation leads to the formation of an exciton, which can undergo charge separation at an interface between the electron-donating MDMO-PPV and the electron-accepting PCNEPV. The electrons and holes formed in this way must escape from each other to contribute to the photoconductivity. The photoconductivity of the blends is found to increase by almost two orders of magnitude upon thermal annealing for three hours at 100 °C. This increase is attributed to the occurrence of phase separation in the polymer/polymer film, resulting in PCNEPV-rich parts. The formation of PCNEPV-rich parts allows the electron to diffuse away from the interface, which favors escape from geminate recombination, leading to a higher photoconductivity. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text