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Information × Registration Number 0219U102083, 0115U004243 , R & D reports Title Hybrid photosensitive composites based on organic dyes and nanocarbon structures popup.stage_title Head Ishchenko Oleksandr O., Registration Date 18-12-2019 Organization Institute of Organic Chemistry NAS of Ukraine popup.description2  A simple technique affording preparation of macroscopic amounts (tens of grams) of nanographite (NG) from the available thermally expanded graphite has been developed. Chemical functionalizations of the obtained NG have been carried out in order to modify its binding properties. Stable suspensions of NG and its derivative modifications have been obtained in water and organic solvents. It is found that cationic, anionic, and merocyanine polymethine dyes do not bind efficiently with the surface of the NGs under study. Under the same conditions, carbon nanotubes (CNTs) of different types — single-, double-, and multi-walled — form stable associates with polymethine dyes of different ionicity, which is primarily manifested by a decrease in the intensity of the dye’s absorption in time, as well as by additional stabilization of the nanotube suspension in case of ionic polymethines. The performed DFT calculations demonstrate that the studied dyes indeed should not bind strongly with NG, yet they can enter the inner cavity of CNTs thus forming more stable aggregates. It is revealed that the interaction of polymethine dyes with detonation nanodiamonds (DNDs) ensue from electrostatic forces. Therefore, adsorption occurs only if the total charge of the chromophore species is negative. For all studied dyes, binding to nanoparticles is accompanied by a bathochromic shift and a decrease in the intensity of their long-wavelength absorption and fluorescence bands. The former is most probably due to an increase in the local refractive index upon adsorption. The latter can be explained both by the vibrational intermolecular transfer of the excitation energy from a dye to the nanoparticle and by the presence of spin-active defects in nanodiamonds. An analysis of the dyes adsorption on the DND particles using the Küster-Freundlich and Langmuir equations has allowed us to determine the adsorption constants and estimate the specific area of the DND aggregates in the hydrosol. Product Description popup.authors Ishchenko Oleksandr O. Korduban Oleksandr M. Kulinich Andrii V. Kurdiukova Iryna V. Lysyuk Lyudmyla S. Ogenko Volodymyr M. Kharkova Liudmyla B. Shandura Mykola P. Yanko Oleg G. popup.nrat_date 2020-04-02 Close