Cooling rate effects on luminescence and structure properties of the 5CB liquid crystal, doped by different nanoparticle dispersions.

The effect of the 5CB liquid crystal cooling rate on its luminescence spectra at the low temperature (T = 4.2 K) has been found and studied for two types of nanocomposites: 5CB liquid crystal, doped by carbon nanotubes (NT) or so-called hybrid nanoparticles (NT + OMMT). Hybrid nanoparticles were prepared from organomodified layered montmorillonite minerals (OMMT) with the addition of carbon nanotubes. Experiments have been carried out at two cooling rates, 2 and 10 K/min. Structure of the luminescence spectral bands is associated with 5CB crystallization peculiarities and formation of its glass-like state under different cooling regimes of the isotropic phase. The reasons for the short-wavelength shifts of the luminescence peaks for the 5CB–(NT + OMMT) sample compared to the 5CB–NT one are discussed. [ABSTRACT FROM AUTHOR]