Figure 2: Physical characterization of epitaxial growth of NaReF4 NCs.
From: Three-dimensional controlled growth of monodisperse sub-50 nm heterogeneous nanocrystals
(a) NaYF4 core and homogenous NaYF4 NCs after epitaxial growth of NaYF4 in longitudinal direction with 0.5 mmol NaOH and 9.5 mmol OA at 310 °C for 1 h; (b) five-section and seven-section ‘bamboo-shaped’ NaYF4/NaGdF4 NRs formed by successive heterogeneous growth of periodical shells of NaGdF4–NaYF4 and NaGdF4–NaYF4–NaGdF4 onto NaYF4 core in the longitudinal direction, with 0.5 mmol NaOH and 0.4 mmol KOH and 9.5 mmol OA at 310 °C. Upper part of the panel shows elemental mapping of Y and Gd; (c) NaYF4 core and heterogeneous NaYF4/NaGdF4 NCs after epitaxial growth of NaGdF4 in the transversal direction with 0.15 mmol NaOH and 19 mmol OA at 290 °C for 3 h; the dimensions of individual nanocrystal were analysed statistically and included in the Supplementary Figs 10, 20–24. Scale bar, 50 nm.
