After explosive growth of efficiency in organic solar cells (OSCs), achieving ideal morphology of bulk heterojunction remains crucial and challenging for advancing OSCs into consumer market. Herein, by utilizing the amphiphobic nature and temperature-dependent miscibility of fluorous solvent, hot fluorous solvent soaking method is developed to optimize the morphology with various donor/acceptor combinations including polymer/small-molecule, all-polymer and all-small-molecule systems. By immersing blend film into hot fluorous solvent which is utilized as liquid medium with better thermal conductivity, the molecular reorganization is accelerated. Furthermore, fluorous solvent can be miscible with the residue of chloroform and chloronaphthalene above upper critical solution temperature. This mixed solvent diffuses around inside the active layer and selectively promotes molecular reorganization, leading to optimized morphology. Compared to widely-used thermal annealing, this approach processed under mild conditions achieves superior photovoltaic performance, indicating the practicality and universality for morphological optimization in OSCs as well as other optoelectronic devices.

Semitransparent superoleophobic coatings with low sliding angles for hot liquids are successfully prepared by fabrication of silica nanotubes on glass slides, and then modification with 1H,1H,2H,2H-perfluorodecyltrichlorosilane.

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Organic optoelectronic devices exhibit distinctive photoresponse to the near-infrared (NIR) light and show great potential in many fields. However, the optoelectronic properties of the existing devices hardly meet the technical requirements of new applications such as energy conversion and health sensing, thus raising the demand to develop high-performance NIR organic semiconductors. To address this issue, a new NIR material, namely, BFIC, is designed and synthesized by inserting fluorothieno­[3,4-b]­thiophene (FTT) as a π-bridge. Since the introduction of FTT can extend the conjugation, stabilize the quinoid resonant structure, and enhance the intramolecular charge transfer, BFIC displays a broad and intense absorption in the NIR region, ranging from 700 to 1050 nm. As a result, the organic solar cell based on BFIC and a polymer donor PTB7-Th realizes a power conversion efficiency of 10.38%. The semitransparent organic solar cell (OSC) shows a power conversion efficiency of 6.15%, accompanied by an average visible transmittance of 38.79% due to the selective photoresponse in the NIR range. The organic photodetector based on PTB7-Th:BFIC delivers a broad spectral response ranging from 330 to 1030 nm with a specific detectivity over 1013 Jones under the self-powered mode, which is one of the highest detectivities among the broad-band organic photodetectors.