Low Voltage‐Loss Organic Solar Cells Light the Way for Efficient Semitransparent Photovoltaics
Abstract
Organic solar cells that are transparent to visible light are highly desirable for applications such as window treatments or solar greenhouse panels. A key challenge is to simultaneously transmit most photons between 400 and 700 nm while retaining a high short‐circuit current and power conversion efficiency (PCE). Here, organic bulk heterojunction (BHJ) solar cells consisting of a donor polymer (PM2) is reported and the non‐fullerene acceptor ITIC‐Th achieves a PCE of 9.3%, and the BHJ thin films exhibit an average visible transmittance over 40%. This value is achieved primarily due to a very high open‐circuit voltage (VOC) of 0.93 V, which represents a voltage loss of only 0.50 V relative to the material optical bandgap, Eopt. In PM2:PC61BM devices, this voltage loss increases to 0.62 V (VOC = 0.82 V). It is found that this difference in VOC is due to higher nonradiative recombination in the fullerene‐based solar cell, suggesting that non‐fullerene acceptors may lead to better performance in semi‐transparent devices. The optoelectronic properties associated with PM2:ITIC‐Th and PM2:PC61BM blends are further corroborated by different morphological features and local structures at the donor‐acceptor interfaces characterized by atomic force microscopy, X‐ray scattering, and solid‐state NMR spectroscopy techniques.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 16, 2022
- Source ID
- 10.1002/solr.202200135
Entities
People
- Akchheta Karki
- Benjamin R. Luginbuhl
- Bradley F Chmelka
- G N Manjunatha Reddy
- Guillermo C. Bazan
- Harald Ade
- Huawei Hu
- Martin Seifrid
- Ming Wang
- Niva A. Ran
- Seo‐Jin Ko
- Shona M. Becwar
- Takashi Okubo
- Thuc-Quyen Nguyen
Organizations
- Donghua University
- Kindai University
- National Science Foundation
- North Carolina State University
- Office of Naval Research
- University of California
- University of California, Santa Barbara