Key Tradeoffs Limiting the Performance of Organic Photovoltaics
Publisher DOI
Abstract
2017 saw the publication of several new material systems that challenge the long-held notion that a driving force is necessary for efficient exciton dissocia-tion in organic photovoltaics (OPVs) and that a loss of ≈0.6 eV between the energy of the charge transfer state Ect and the energy corresponding to open circuit is general. In light of these developments, the authors combine insights from device physics and spectroscopy to review the two key tradeoffs limiting OPV performances. These are the tradeoff between the charge carrier generation efficiency and the achievable open circuit voltage (Voc) and the tradeoff between device thickness (light absorption) and fill factor. The emergence of several com-petitive nonfullerene acceptors (NFAs) is exciting for both of these. The authors analyze what makes these materials compare favorably to fullerenes, including the potential role of molecular vibrations, and discuss both design criteria for new molecules and the achievable power conversion efficiencies.
Date Issued
2018
Publication Type
Article
Language(s)
en
Author(s)
Ramirez, Ivan | |
Causa, Martina | |
Riede, Moritz |
Additional Credits
Journal
Advanced energy materials
Publisher
Wiley
ISSN
1614-6832
Access(Rights)
restricted