Modelling of polymer-carbon nanotube heterojunctions for photovoltaic applications

  1. GLANZMANN, LIVIA NOEMI
unter der Leitung von:
  1. Angel Rubio Secades Doktorvater/Doktormutter
  2. Duncan John Mowbray Doktorvater/Doktormutter

Universität der Verteidigung: Universidad del País Vasco - Euskal Herriko Unibertsitatea

Fecha de defensa: 31 von Januar von 2017

Gericht:
  1. Paola Ayala Präsident/in
  2. Nerea Zabala Unzalu Sekretär/in
  3. Larry Lüer Vocal
  4. Vito Despoja Vocal
Fachbereiche:
  1. Polímeros y Materiales Avanzados: Física, Química y Teconología

Art: Dissertation

Teseo: 121521 DIALNET lock_openADDI editor

Zusammenfassung

Semiconducting single-walled carbon nanotubes (s-SWNT) are promising materialsfor efficient organic photovoltaics (OPVs). Unfortunately, the implementation of s-SWNTs has so far not lead to the expected increase in power conversion efficienciesof OPVs. For this reason, we want to study the electronic processes within polymer-SWNT heterojunctions. Transient spectroscopy provides direct information aboutphotoexcitation processes in blends. We modelled the transient spectrum of apolymer:fullerene:s-SWNT blend using Linear Response. Based on our results, weare able to explain the structure transient spectra of s-SWNT systems and theelectronic dynamics linked to it. Further, we studied the internal quantum efficiencyof different donor/acceptor blends by carrying out calculations of the Landauer-Bütticker conductance of prototypical donor/acceptor heterojunctions. We find adependence of the conductivity on the level alignment. By improving the levelalignment of the polymer and SWNT through the use of larger band gap SWNTs,one may obtain a dramatic improvement in OPV efficiency. In summary, our resultsprovide a deeper insight into the photoexcitation and electronic processes ofpolymer-carbon nanotube heterojunctions and thus support the development of moreefficient polymer-SWNT OPVs.