Xue Zhang

Bio: Xue Zhang is an academic researcher from Wuhan University of Technology. The author has contributed to research in topics: Organic solar cell. The author has an hindex of 1, co-authored 1 publications receiving 38 citations.

13.9% Efficiency Ternary Nonfullerene Organic Solar Cells Featuring Low-Structural Order

Abstract: The insufficient phase separation between polymer donors and nonfullerene acceptors (NFAs) featuring low structural order disrupts efficient charge transport and increases charge recombination, con...

Aggregation of non-fullerene acceptors in organic solar cells

Abstract: Organic solar cells (OSCs) employing non-fullerene acceptors (NFAs) have drawn significant research attention in recent years. Molecular stacking and aggregation of electron donors and acceptors within the photoactive layer is vitally important for light absorption and the photon-to-electricity conversion process. Herein, we present the versatile molecular stacking of the state-of-the-art NFAs, as well as the affecting factors including the chemical structures of NFAs and physical processing conditions. We highlight in particular experimental approaches to regulate molecular stacking and aggregation and summarize the influences of these features on optoelectronic and photovoltaic properties of NFA-based OSCs, which provide crucial guidance for further development of high performance OSCs.

High-Performance Ladder-Type Heteroheptacene-Based Nonfullerene Acceptors Enabled by Asymmetric Cores with Enhanced Noncovalent Intramolecular Interactions.

Abstract: Nonfullerene acceptors (MQ3, MQ5, MQ6) are synthesized using asymmetric and symmetric ladder-type heteroheptacene cores with selenophene heterocycles. Although MQ3 and MQ5 are constructed with the same number of selenophene heterocycles, the heteroheptacene core of MQ5 is end-capped with selenophene rings while that of MQ3 is flanked with thiophene rings. With the enhanced noncovalent interaction of O⋅⋅⋅Se compared to that of O⋅⋅⋅S, MQ5 shows a bathochromically shifted absorption band and greatly improved carrier transport, leading to a higher power conversion efficiency (PCE) of 15.64 % compared to MQ3, which shows a PCE of 13.51 %. Based on the asymmetric heteroheptacene core, MQ6 shows an improved carrier transport induced by the reduced π-π stacking distance, related with the increased dipole moment in comparison with the nonfullerene acceptors based on symmetric cores. MQ6 exhibits a PCE of 16.39 % with a VOC of 0.88 V, a FF of 75.66 %, and a JSC of 24.62 mA cm-2 .