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Nanostructures in the form of 1.2-nm-thick colloidal CdSe nanoplatelets rolled into scrolls are investigated. The morphology of these scrolls is analysed and their basic geometric parameters are determined (diameter 29 nm, longitudinal size 100 -150 nm) by TEM microscopy. Absorption and photoluminescence spectra of these objects are recorded, and the luminescence decay kinetics is studied. It is shown that the optical properties of CdSe nanoscrolls differ significantly from the properties of CdSe quantum dots and that these nanoscrolls are attractive for nanophotonic devices due to large oscillator strengths of the transition, small widths of excitonic peaks and short luminescence decay times. Nanoscrolls can be used to design hybrid organic -inorganic pure-color LEDs with a high luminescence quantum yield and low operating voltages.

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CdS colloidal nanocrystals with an average size of 4.5 nm and oleic acid as surfactant were studied using photoluminescence spectroscopy and time-correlated single photon counting technique at different temperatures. Observed spectra revealed three thermally activated luminescence bands at 2.15, 1.76, and 1.37 eV in addition to conventional band edge recombination of the nanocrystals. We present a kinetic model based on concept of single emitters which quantitatively describes the luminescence of the ensemble of the nanocrystals in the temperature range 10–300 K. We determined activation energies (18.2 and 8.6 meV) for transitions responsible for the luminescence. The 1.76 eV band most probably emerges from the intrinsic defects on the surface of CdS, whereas bands at 2.15 and 1.37 eV result from the influence of oleic acid bonded to the surface of the nanocrystals.

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