Transmission electron microscopy and Monte Carlo simulations of ordering in Au-Cu clusters produced in a laser vaporization source

Truncated-octahedral copper-gold nanoparticles

“…The measurement of the d-spacing of the (111) family of planes gives an estimate of 3.78 Å for the lattice parameter of the two particles in Figure 2. This value is close to the lattice parameter of 3.76 Å for the stoichiometric (Cu 3 Au) M nanoparticles in the previous work [5]. Figure 3 shows an aggregation of two TO particles.…”

“…In fact, structural rearrangements in gold nanoparticles induced by an electron beam have been reported previously [11]. In another previous work, Cu-Au nanoparticles, which were produced by laser vaporization and deposited on an amorphous carbon film, also exhibited hexagonal 2D-projections under HRTEM [5]. The stable 3D morphology of the particles is identified as a truncatedoctahedron (TO) which is geometrically constructed by the uniform removal of six square pyramids from the six vertices of a regular octahedron.…”

“…Decahedral and icosahedral Cu-Au alloy particles were produced by an electrochemical method and investigated by TEM [4]. In other work, decahedral and truncated octahedral morphologies were found for 1-4.5 nm-sized Cu-Au nanoparticles produced by laser vaporization of the bulk stoichiometric alloys CuAu, Cu 3 Au, and CuAu 3 and then deposition on amorphous carbon and MgO substrates [5]. These nanoparticles all have fcc structures.…”

“…Alloying between Cu and Au is not only well known for bulk systems [6] but also for nano-scale systems [2][3][4][5]. The dissolution of copper atoms in gold nanoparticles supported on an amorphous carbon film was observed using Transmission Electron Microscopy (TEM) [2].…”

“…Among the various bimetallic nanoparticles which have potential applications in optics, catalysis and nano-electronics [1], Cu-Au nanoparticles have been studied by many research groups since the early 1990s [1][2][3][4][5].…”