Unraveling Intermolecular Interactions in Non-Fullerene Acceptor Based Polymer Solar Cells for Manufacturing

reportActive / Technical Report | Accesssion Number: AD1147714 | Open PDF

Abstract:

At the beginning of this project (2016), device efficiencies for OPVs made using conjugated donor polymers and non-fullerene acceptors (NFAs) were near 11%. Now, reported efficiencies for new systems exceed 18%, since both polymer donor and molecular acceptor can be tuned to a wide variety of properties and successively iterated on. Over the last few years with this project, we have explored a number of structure-property relationships that stemmed from PCBM-based systems and have evolved into NFA-based systems. In general, we have looked to answer fundamental questions that will help understand the requirements for high-performing and easily processable non-fullereneacceptor systems: 1) What is the nature of charge transfer and charge separation in comparison with fullerenes? 2) What are the morphological differences between polymer:fullerene and polymer:NFA blend films, and how are those differences reflected in the device performance? 3) What polymer properties, such as aggregation and crystallinity, affect the blending process with PCBM vs. NFAs? 4) What is the underlying reason for different active layer thickness tolerances in polymer:NFA blends? 5) How does the donor:acceptor HOMO level offset effect solar cell performance? Understanding these fundamental issues has shed light on the NFA chemistry and has guided the design of polymer donors and NFA molecules for organic solar cells. Further, we have carried this work out using ambient atmosphere roll-to-roll compatible blade coating methods we have developed such that the results obtained in this program will be directly applicable to manufacturing pertaining to this new class of materials. We have leveraged the longestablished collaboration of the SoRey group to carry out the chemistry/physics/ materials/device research, supplemented by synthetic consultation with members of the Marder group at University of Colorado (previously Georgia Tech).

Author(s):
Reynolds, John R.
Author Organization(s):
Georgia Institute of Technology
Funding Organization(s):
Office of Naval Research, Arlington , VA
Document Type:
Technical Report/Final Report
Publication Date:
2021 Sep 13
Pagination:
23

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution Code:
A - Approved For Public Release
Distribution Statement: Public Release

RECORD

Collection: TRECMS
Identifying Numbers
Grant Number(s):
N00014-17-1-2243
Subject Terms
Modernization Areas:
Microelectronics
Communities of Interest:
Energy and Power Technologies
Descriptor(s):
quantum efficiency, solar cells, copolymers, organic solar cells, density functional theory, transition temperature, scattering, thin films, x rays, advanced materials, chemistry, conjugated polymers, diseases and disorders, dissociation, electrons, engineering, field effect transistors
Keyword(s):
Intermolecular Interactions, nfa (non-fullerene acceptors), nfa Based Polymer Solar Cells, charge separation, polymer properties, morphology, active layer thickness tolerances, photovoltaic performance, donor acceptor HOMO level, homo (highest occupied molecular orbital), Discrete molecule ordering
Subject Categories:
Power Production and Energy Conversion (Nonpropulsive); Materials; Physics
Creation Date:
2021 Sep 29
Update Date:
2021 Dec 06