Synthesis and high pressure studies of white luminescence host-guest complex nanocrystals based on C and p-But-calix[8]arene.

Host-guest structured nanocrystals consisting of p-But-calix[8]arene and fullerene C were fabricated with the facial solution deposition method. The as-prepared host-guest complex nanocrystals are well crystallized in a tetragonal structure, in which the guest C and host p-But-calix[8]arene molecules interact with each other via the van der Waals force. The host-guest crystal has a wider band gap compared to that of C crystals. The luminescence range of the host-guest structured nanocrystals was widely extended, and its photoluminescence (PL) intensity was highly enhanced by one order of magnitude. High pressure studies on such host-guest nanocrystals were carried out using the diamond anvil cell technique with the associated spectroscopic measurements. Raman and PL spectra show a phase transition occurred on the samples owing to the deformation of fullerene molecules. A PL behavior change was also observed synchronously with the phase transition. The host-guest structure strongly influences the structure and optical behaviors of C under pressure.