Abstract
Au nanocondensates in the form of amorphous clusters, multiply twinned particles (MTPs), and face-centered cubic (fcc) structures with progressively larger particle size, as characterized by transmission electron microscopy (TEM), were fabricated by pulsed laser ablation on Au in vacuum with or without argon gas flow at 1.5 × 108 versus 1.4 × 1012 W/cm2 power density for a rapid heating/cooling effect. The observed critical size, ca. 2 nm, for the amorphous to MTP transformation implies a minimum {111} surface area of ca. 4 nm2 for MTP. Coarsening and {111}-specific coalescence of the MTPs and fcc to form defects are competitive under the influence of laser parameters and Ar gas flow. In situ TEM observations further indicated that the MTP → fcc transformation occurred for a surprisingly small particle size of 5 nm due to the catalytic effect of graphite-like materials (G) with varied extent of rolling following the habit plane (0001)G/(111)fcc. The ultimate relationship would be (2110)G//(211)fcc; [0...
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
