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Updated: Jul 13, 2025

Fabrication of Fully Solution Processed Inorganic Nanocrystal Photovoltaic Devices

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Published on: July 8, 2016

Optimized Crystal Framework by Asymmetric Core Isomerization in Selenium-Substituted Acceptor for Efficient Binary

Can Yang¹, Qiaoshi An¹, Mengyun Jiang¹

¹Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, China.

Angewandte Chemie (International Ed. in English)

|October 12, 2023

Summary

Researchers engineered novel selenium-containing small molecular acceptors (SMAs) for organic solar cells (OSCs). The optimized A-OSeF molecule achieved a record 18.5% power conversion efficiency in binary OSC devices.

Keywords:

Asymmetric Acceptors Crystal Engineering Isomerization Selenium Solar Cells

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Published on: January 10, 2017

Area of Science:

Materials Science
Organic Electronics
Photovoltaics

Background:

Small molecular acceptors (SMAs) are crucial for organic solar cell (OSC) efficiency.
Both structural isomerization and selenium substitution in SMAs impact device performance.
The synergistic effects of these modifications are not fully understood.

Purpose of the Study:

To investigate the combined effects of regional isomerization and selenium substitution in SMAs.
To develop novel SMAs with enhanced properties for efficient OSCs.
To establish structure-property relationships for selenium-containing SMAs.

Main Methods:

Synthesis of three isomeric SMAs (S-CSeF, A-ISeF, A-OSeF) with varied selenium positions and heteroaromatic rings.
Crystallographic analysis of A-OSeF to understand molecular packing.
Fabrication and characterization of OSC devices using the developed SMAs.
Analysis of film morphology, band gap, crystallinity, and charge mobility.

Main Results:

A-OSeF exhibited closer π-π stacking and more ordered 3D network packing.
Outward shift of selenium substitution led to wider band gaps, higher crystallinity, and improved electron mobility.
PM1:A-OSeF blend showed favorable fibrous morphology with ordered packing and efficient charge transport.
A-OSeF-based devices achieved a record 18.5% power conversion efficiency in binary OSCs.

Conclusions:

Precise molecular engineering of selenium position and heteroaromatic rings offers a synergistic approach.
Optimized molecular packing and charge transport are key to high-performance OSCs.
This work provides a promising strategy for developing top-ranked selenium-containing SMAs for OSC applications.