Fig. 3: Self-assembled binary Laves SPs.

(a) Schematic illustration of the formation of Laves phase binary SPs via a drying emulsion droplet method. (b) 2D HAADF-STEM image of a self-assembled SP with the core-shell structure highlighted by yellow dashed circles. 2D HAADF-STEM projections of (c) a 115 nm-sized SP, (d) a 150 nm-sized SP and (e) a SP for EDX chemical mapping study projection. Superimposition of (f) Pb and Cd and (g) of Pb, Cd and Se. Magenta, cyan and yellow represent the distribution of Pb, Cd and Se, respectively. Structure model of a perfect MgZn₂ SP viewed along the (h) [0001], (i) [21\(\bar{3}\)0] and (j) [11\(\bar{2}\)0] projections, respectively. Sparse Sphere Reconstruction (SSR)³⁹ renderings of (k)–(m) a 115 nm-sized SP and (n)–(p) a 150 nm-sized SP viewed along the (k), (n) [0001], (l), (o) [21\(\bar{3}\)0] and (m), (p) [11\(\bar{2}\)0] projections, respectively. Stacking faults in the two SPs are marked with dark blue dashed lines. A digital micrograph of an SP dispersion excited by ultraviolet light (wavelength λ = 405 nm) as an inset of (a)iv, showing photoluminescence of the SP dispersion at room temperature. Scale bars: 50 nm (b), 20 nm (c), 20 nm (d), 80 nm (e)–(g). The transparency of the binary species (k)–(p) was increased for visual clarity. For interactive 3D views of the 115 nm and 150 nm SPs, see Supplementary Data 4–5.