Non-fullerene fused-ring electron acceptors boost the power conversion efficiency of organic solar cells, but they suffer from high synthetic cost and low yield. Here, we show a series of low-cost noncovalently fused-ring electron acceptors, which consist of a ladder-like core locked by noncovalent sulfur–oxygen interactions and flanked by two dicyanoindanone electron-withdrawing groups. Compared with that of similar but unfused acceptor, the presence of ladder-like structure markedly broadens the absorption to the near-infrared region. In addition, the use of intramolecular noncovalent interactions avoids the tedious synthesis of covalently fused-ring structures and markedly lowers the synthetic cost. The optimized solar cells displayed an outstanding efficiency of 13.24%. More importantly, solar cells based on these acceptors demonstrate very low non-radiative energy losses. This research demonstrates that low-cost noncovalently fused-ring electron acceptors are promising to achieve high-efficiency organic solar cells.

Arecordpower conversion efficiency of 8.40 %was obtained in single-component organic solar cells (SCOSCs) based on double-cable conjugated polymers.T his is realized based on exciton separation playing the same role as charge transport in SCOSCs.T wo double-cable conjugated polymers were designed with almost identical conjugated backbones and electron-withdrawing side units,b ut extra Cl atoms had different positions on the conjugated backbones.W hen Cl atoms were positioned at the main chains,the polymer formed the twist backbones,e nabling better miscibility with the naphthalene diimide side units.T his improves the interface contact between conjugated backbones and side units,resulting in efficient conversion of excitons into free charges.T hese findings reveal the importance of charge generation process in SCOSCs and suggest as trategy to improve this process: controlling miscibility between conjugated backbones and aromatic side units in double-cable conjugated polymers.

A series of alkyl, alkoxyl, and alkylthio substituted A–π–D–π–A type nonfullerene acceptors (NFAs) IDTCN‐C, IDTCN‐O, and IDTCN‐S are designed and synthesized. The introduction of a lateral side chain at the outer position of the π bridge unit can endow the terminal moiety with a confined planar conformation due to the steric hindrance. Thus, compared with nonsubstituted NFA (IDTT2F), these acceptors tend to form favorable face‐on orientation and exhibit strong crystallinity as verified with grazing‐incidence wide‐angle X‐ray scattering measurement. Moreover, the variation of side chain can significantly change the lowest unoccupied molecular orbital (LUMO) energy level of acceptors. As state‐of‐the‐art NFAs, a power conversion efficiency of 13.28% (Voc = 0.91 V, Jsc = 19.96 mA cm−2, and FF = 73.2%) is obtained for the as‐cast devices based on IDTCN‐O, which is among the highest value reported in literature. The excellent photovoltaic performance for IDTCN‐O can be attributed to its slightly up‐shifted LUMO level and more balanced charge transport. This research demonstrates side chain engineering is an effective way to achieve high efficiency organic solar cells.

Organic solar cells (OSCs) have attracted increasing attention due to their advantages of a low-cost, lightweight, rollable, and large-area fabrication. [1] Due to efforts in material design and device optimization, the efficiency of the single-junction OSCs has rapidly increased in recent years. [2] The photovoltaic materials (organic semiconductors) in OSCs must first absorb as

Miniaturization of spectrometers can be achieved using an array of narrowband photodetectors responsive at specific wavelengths. In this work, sensitive organic narrowband photodetectors with tunable spectral response in the near-infrared (NIR) wavelength range are demonstrated. This is achieved using a resonant optical-cavity device architecture based on a thick ZnO spacer to increase the weak NIR absorption of a low-band gap conjugated polymer containing [1,2,5]selenadiazolo [3,4-c]pyridine. We realize spectral response full-width at half-maximum (FWHM) values down to 22 nm and achieve calculated peak specific detectivity (D*) over 10 11 Jones in these cavity-enhanced photodetectors. More importantly, we achieve continuously tuned detection wavelengths over a wide wavelength range of 660−1510 nm. This allows for a proof-of-concept demonstration of a miniaturized spectrometer for the NIR wavelength range and can resolve the NIR characteristic absorption bands of water, ethanol, and acetone.

Arecordpower conversion efficiency of 8.40 %was obtained in single-component organic solar cells (SCOSCs) based on double-cable conjugated polymers.T his is realized based on exciton separation playing the same role as charge transport in SCOSCs.T wo double-cable conjugated polymers were designed with almost identical conjugated backbones and electron-withdrawing side units,b ut extra Cl atoms had different positions on the conjugated backbones.W hen Cl atoms were positioned at the main chains,the polymer formed the twist backbones,e nabling better miscibility with the naphthalene diimide side units.T his improves the interface contact between conjugated backbones and side units,resulting in efficient conversion of excitons into free charges.T hese findings reveal the importance of charge generation process in SCOSCs and suggest as trategy to improve this process: controlling miscibility between conjugated backbones and aromatic side units in double-cable conjugated polymers.

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