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Tuning photoluminescence of organic rubrene nanoparticles through a hydrothermal process

Mi Suk Kim1, Eun Hei Cho1, Dong Hyuk Park12, Hyunjung Jung2, Joona Bang2 and Jinsoo Joo1*

Author Affiliations

1 Department of Physics, Korea University, Anam-dong, Seongbuk-gu, Seoul 136-713, Korea

2 Department of Chemical & Biological Engineering, Korea University, Anam-dong, Seongbuk-gu, Seoul 136-713, Korea

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Nanoscale Research Letters 2011, 6:405  doi:10.1186/1556-276X-6-405

Published: 1 June 2011


Light-emitting 5,6,11,12-tetraphenylnaphthacene (rubrene) nanoparticles (NPs) prepared by a reprecipitation method were treated hydrothermally. The diameters of hydrothermally treated rubrene NPs were changed from 100 nm to 2 μm, depending on hydrothermal temperature. Photoluminescence (PL) characteristics of rubrene NPs varied with hydrothermal temperatures. Luminescence of pristine rubrene NPs was yellow-orange, and it changed to blue as the hydrothermal temperature increased to 180°C. The light-emitting color distribution of the NPs was confirmed using confocal laser spectrum microscope. As the hydrothermal temperature increased from 110°C to 160°C, the blue light emission at 464 to approximately 516 nm from filtered-down NPs was enhanced by H-type aggregation. Filtered-up rubrene NPs treated at 170°C and 180°C exhibited blue luminescence due to the decrease of intermolecular excimer densities with the rapid increase in size. Variations in PL of hydrothermally treated rubrene NPs resulted from different size distributions of the NPs.