Single‐Junction Organic Photovoltaic Cell with 19% Efficiency

Abstract

Improving power conversion efficiency (PCE) is important for broadening the applications of organic photovoltaic (OPV) cells. Here, a maximum PCE of 19.0% (certified value of 18.7%) is achieved in single‐junction OPV cells by combining material design with a ternary blending strategy. An active layer comprising a new wide‐bandgap polymer donor named PBQx‐TF and a new low‐bandgap non‐fullerene acceptor (NFA) named eC9‐2Cl is rationally designed. With optimized light utilization, the resulting binary cell exhibits a good PCE of 17.7%. An NFA F‐BTA3 is then added to the active layer as a third component to simultaneously improve the photovoltaic parameters. The improved light unitization, cascaded energy level alignment, and enhanced intermolecular packing result in open‐circuit voltage of 0.879 V, short‐circuit current density of 26.7 mA cm−2, and fill factor of 0.809. This study demonstrates that further improvement of PCEs of high‐performance OPV cells requires fine tuning of the electronic structures and morphologies of the active layers.

Impact of substituents on the performance of small-molecule semiconductors in organic photovoltaic devices via regulating morphology

“…Organic photovoltaic technologies have experienced a marked development in recent years, 1 achieving an excellent power conversion efficiency (PCE) of 19% in a single-junction cell. 2 This progress was largely enabled by the creation of new organic semiconductors (SCs) comprising a meticulously designed π-conjugated backbone, as typified by recent non-fullerene n-type (or acceptor) SCs bearing a highly ring-fused core unit flanked by strongly electron-withdrawing end groups. 3–8 In general, active layers of organic photovoltaic devices (OPVs) are composed of p-type (or donor) and n-type SCs to form the p/n interface ( i.e.…”

Molecular optimization of incorporating pyran fused acceptor–donor–acceptor type acceptors enables over 15% efficiency in organic solar cells

“…32–40 However, so far, OSCs surpassing 18% power conversion efficiency (PCE) have been almost entirely based on Y6 and its analogues. 41–44 Besides the relatively ossified structures of the Y6 system, it is highly possible that lots of other distinctive A–D–A skeleton-based NFAs could achieve high-efficiency OSCs. 31,34,45 Therefore, it is very necessary to explore other types of NFAs with the aim of achieving state-of-the-art OSCs and beyond.…”

Stable dinitrile end-capped closed-shell non-quinodimethane as a donor, an acceptor and an additive for organic solar cells

“…35 By selecting an appropriate third component, PCEs more than 18% have been reported for efficient ternary OSCs, which indicates tremendous potential for development. 36–42…”