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Title: Designing Alternative Non‐Fullerene Molecular Electron Acceptors for Solution‐Processable Organic Photovoltaics
Abstract

Until recently, solution‐processable organic photovoltaics (OPVs) mainly relied on fullerene derivatives as then‐type material, paired with ap‐type conjugated polymer. However, fullerene derivatives have disadvantages that limit OPV performance, thus fueling research of non‐fullerene acceptors (NFAs). Initially, NFAs showed poor performance due to difficulties in obtaining favorable blend morphologies. One example is our work with 2,6‐dialkylamino core‐substituted naphthalene diimides. Researchers then learned to control blend morphology by NFA molecular design. To limit miscibility with polymer while preventing excessive self‐aggregation, non‐planar, twisted or 3D structures were reported. An example of a 3D structure is our work with homoleptic zinc(II) complexes of azadipyrromethene. The most recent design is a planar A‐D‐A conjugated system where the D unit is rigid and has orthogonal side chains to control aggregation. These have propelled power conversion efficiencies (PCEs) to ∼14 %, surpassing fullerene‐based OPVs. These exciting new developments prompt further investigations of NFAs and provide a bright future for OPVs.

 
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Award ID(s):
1148652
NSF-PAR ID:
10083651
Author(s) / Creator(s):
 
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
The Chemical Record
Volume:
19
Issue:
6
ISSN:
1527-8999
Page Range / eLocation ID:
p. 1078-1092
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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