13.4 % Efficiency from All-Small-Molecule Organic Solar Cells Based on a Crystalline Donor with Chlorine and Trialkylsilyl Substitutions
Journal article, 2021

How to simultaneously achieve both high open-circuit voltage (Voc) and high short-circuit current density (Jsc) is a big challenge for realising high power conversion efficiency (PCE) in all-small-molecule organic solar cells (all-SM OSCs). Herein, a novel small molecule (SM)-donor, namely FYSM−SiCl, with trialkylsilyl and chlorine substitutions was designed and synthesized. Compared to the original SM-donor FYSM−H, FYSM−Si with trialkylsilyl substitution showed a decreased crystallinity and lower highest occupied molecular orbital (HOMO) level, while FYSM−SiCl had an improved crystallinity, more ordered packing arrangement, significantly lower HOMO level, and predominant “face-on” orientation. Matched with a SM-acceptor Y6, the FYSM−SiCl-based all-SM OSCs exhibited both high Voc of 0.85 V and high Jsc of 23.7 mA cm−2, which is rare for all-SM OSCs and could be attributed to the low HOMO level of FYSM−SiCl donor and the delicate balance between high crystallinity and suitable blend morphology. As a result, FYSM−SiCl achieved a high PCE of 13.4 % in all-SM OSCs, which was much higher than those of the FYSM−H- (10.9 %) and FYSM−Si-based devices (12.2 %). This work demonstrated a promising method for the design of efficient SM-donors by a side-chain engineering strategy via the introduction of trialkylsilyl and chlorine substitutions.

organic solar cells

photovoltaics

side chain engineering

crystalline donor

power conversion efficiency

Author

Wenyan Su

Jinan University

Yang Wang

Soochow University

Zhihong Yin

Soochow University

Qunping Fan

Xia Guo

Soochow University

Liyang Yu

Sichuan University

Yuxiang Li

Xi'an University of Science and Technology

Lintao Hou

Jinan University

Maojie Zhang

Soochow University

Qiang Peng

Sichuan University

Yongfang Li

Soochow University

Ergang Wang

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Zhengzhou University

ChemSusChem

1864-5631 (ISSN) 1864-564X (eISSN)

Vol. 14 17 3535-3543

Subject Categories

Other Mechanical Engineering

Other Engineering and Technologies not elsewhere specified

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1002/cssc.202100860

PubMed

34057293

More information

Latest update

4/4/2022 6