Abstract
In this paper we investigate charge carrier recombination processes in polymer based photodetector ITO/PEDOT:PSS/MEH-PPV/Al. The major carriers are the hole polarons created by the photoexcitation in the active MEH-PPV film. The model used in this paper is based on the continuity equation and drift-diffusion equation for hole polarons. We assume the Poole-Frenkel expression for field dependence of the hole polaron mobility. The internal quantum efficiency dependence on incident photon flux density, incident light wavelength and applied electric field is included in the model. The simulated photocurrent density spectra for two different, assumed, recombination mechanisms, linear (monomolecular) and square (bimolecular) is compared with our experimental results. The bimolecular recombination mechanism applied in our model is assumed to be of Langevin type. The agreement between the measured and the calculated data unambiguously indicate that the hole polaron recombination mechanism in the MEH-PPV film is bimolecular with bimolecular rate constant depending on the external electric field. For the established recombination mechanism the theoretical prediction of the photocurrent density spectra shows excellent agreement with the measured spectra in wide range of inverse bias voltages (from 0 to -8 V).
Highlights
In this paper we investigate charge carrier recombination processes in polymer based photodetector ITO/PEDOT:PSS/MEH-PPV/Al
Utvrđeno je da se većinski nosioci naelektrisanja – šupljinski polaroni rekombinuju bimolekularno pri čemu je proces rekombinacije Langevin-ovog tipa
Summary
Izmereni spektar gustine fotostruje detektora poređen je sa teorijski dobijenim spektrom za slučaj monomolekularne i bimolekularne rekombinacije nosilaca. Slaganje eksperimentalnih rezultata sa rezultatima proračuna nedvosmisleno ukazuju da se šupljinski polaroni u polimerskom filmu rekombinuju bimolekularno, pri čemu koeficijent bimolekularne rekombinacije zavisi od jačine električnog polja. Za ustanovljeni tip rekombinacionih procesa modelovani spektar gustine fotostruje pokazuje odlično slaganje sa eksperimentom u širokom opsegu napona inverzne polarizacije (od 0 do –8 V). Bitan aspekt daljeg razvoja polimerskih fotodetektora predstavlja razvoj teorijskih modela koji objašnjavaju fizičke mehanizme elektro- i fotogeneracije nosilaca naelektrisanja, njihovog transporta i rekombinacije u provodnim polimerima.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
