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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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The possibility to enhance the absorbance of ultrathin organic dye films is important for improvement of the efficiency of organic solar cells, heterogeneous photocatalysts and organic electronics devices. Plasmonic nanoparticles (NPs) may serve this purpose due to their well-known ability to boost optical properties of organic molecules trapped in the strong electric field near the surface of light-irradiated NPs. Unlike SERS, surface-enhanced IR absorption and surface-enhanced fluorescence, direct observations of plasmon enhanced absorption (PREA) are difficult due to the difference between magnitudes of extinctions of NPs and molecules. Herein, we report on a novel strategy for significant enhancement of visible light absorption in thin films of organic dyes (mono- and double-decker tetra-15-crown-5-phthalocyanines and 5-carboxytetramethylrhodamine) by using the 2D gold plasmonic antennas with tunable optical properties. The films of dyes were formed by Langmuir-Blodgett technique that allows fabrication of tightly-packed ordered layers [1]. Gold nanostructured antennas with spectral characteristics tuned in a range of 520-660 nm via precise manipulating of plasmon coupling were deposited on the top of organic films [2]. The extinctions of as-formed hybrid systems can be increased by more than 500 percents depending on the thickness and composition of organic layer. For multiband absorption dyes, we demonstrated the wavelength-selective enhancement effect by appropriate shifting of the resonance maximum of the hybrid structure. Our method also makes it possible to convert the narrow-band spectrum of some dyes into the enhanced broadband optical pattern of the hybrid without changing the molecular structure of the dye. We believe that our strategy can be successfully used to design novel function ultrathin materials for various technically relevant applications in organic optoelectronics.