High Efficiency Non-fullerene Organic Tandem Photovoltaics Based on Ternary Blend Subcells

Wenchao Huang; Sheng-Yung Chang; Pei Cheng; Dong Meng; Bowen Zhu; Selbi Nuryyeva; Chenhui Zhu; Lijun Huo; Zhaohui Wang; Mingkui Wang; Yang Yang

doi:10.1021/acs.nanolett.8b03950

High Efficiency Non-fullerene Organic Tandem Photovoltaics Based on Ternary Blend Subcells

Nano Lett. 2018 Dec 12;18(12):7977-7984. doi: 10.1021/acs.nanolett.8b03950. Epub 2018 Dec 3.

Authors

Wenchao Huang^{1

2}, Sheng-Yung Chang^{1

2}, Pei Cheng^{1

2}, Dong Meng^{1

2

3}, Bowen Zhu^{1

2}, Selbi Nuryyeva^{1

2}, Chenhui Zhu⁴, Lijun Huo⁵, Zhaohui Wang³, Mingkui Wang⁶, Yang Yang^{1

2}

Affiliations

¹ Department of Materials Science and Engineering , University of California , Los Angeles , California 90095 , United States.
² California NanoSystems Institute , University of California , Los Angeles , California 90095 , United States.
³ Beijing National Laboratory for Molecular Sciences, Key Laboratory of Organic Solids, Institute of Chemistry , Chinese Academy of Sciences (ICCAS) , Beijing 100190 , P.R. China.
⁴ Advanced Light Source , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States.
⁵ Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, Heeger Beijing Research and Development Center, School of Chemistry , Beihang University , Beijing 100191 , P.R. China.
⁶ Wuhan National Laboratory for Optoelectronics , Huazhong University of Science and Technology , Wuhan 430070 , P.R. China.

PMID: 30475629
DOI: 10.1021/acs.nanolett.8b03950

Abstract

The application of tandem structure that integrates multiple subcells into one device is a promising way to realize high efficiency organic solar cells. However, current-matching among different subcells remains as the main challenge for organic tandem photovoltaics. Here, we provide a facile approach to achieve a good current matching via engineering the chemical composition of non-fullerene ternary blend subcells. For the front subcell, a ternary blend of PDBT-T1:TPH-Se:ITIC is selected due to its good thermal stability. The amorphous nature of TPH-Se can sufficiently suppress the unfavorable phase separation of blends during the heat treatment, enabling a sintering in the fabrication of high quality interconnecting layer. A double-junction tandem device is fabricated with a rear subcell consisting of PBDB-T:ITIC. After the optimization of the chemical composition of the front subcell, the power conversion efficiency (PCE) of double-junction tandem device increased from 10.6% using PDBT-T1:TPH-Se binary front subcell to 11.5% using PDBT-T1:TPH-Se:ITIC (1:0.9:0.1) ternary front subcell due to better current matching. In order to further enhance the light absorption in the near-infrared region, a third junction PBDTTT-EFT:IEICO-4F is introduced. The champion cell of triple-junction non-fullerene tandem solar cell achieves a PCE of 13.0% with a high open circuit voltage of 2.52 V.

Keywords: Organic tandem photovoltaics; current matching; morphology; non-fullerene; ternary subcell.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.
Research Support, Non-U.S. Gov't