In:
Energy & Environmental Science, Royal Society of Chemistry (RSC), Vol. 15, No. 6 ( 2022), p. 2537-2544
Abstract:
Manipulating the donor:acceptor (D:A) energetics, e.g. , the highest occupied molecular orbital (HOMO) offset, is the key to balancing the charge separation and charge recombination for high-performance organic solar cells (OSCs). Herein, we designed and synthesized a non-fullerene electron acceptor, i.e. , BTP-H2, which shows strong intermolecular interaction and near-zero HOMO offset when pairing with polymer donor PM6. Transient absorption spectroscopies unveil that BTP-H2 exhibits a long-lived intra-moiety charge-separation state, which contributes to efficient hole transfer or charge generation, irrespective of the small HOMO offset. In addition, the small energetic offset reduces the non-radiative loss for a high open-circuit voltage ( V oc ). As a result, we demonstrate high-performance OSCs with the best power conversion efficiency (PCE) of 18.5%, a high V oc of 0.932 V and a peak photon-to-electron response of ∼ 90%. Furthermore, ternary OSCs comprising PM6:BTP-H2:L8-BO exhibit a champion PCE of 19.2% (certified value of 18.8%) due to the improved balance between charge generation and charge recombination, and this represents the best among PCEs of single-junction OSCs.
Type of Medium:
Online Resource
ISSN:
1754-5692
,
1754-5706
Language:
English
Publisher:
Royal Society of Chemistry (RSC)
Publication Date:
2022
detail.hit.zdb_id:
2439879-2
