Temperature-dependent formation and shrinkage of hollow shells in hemispherical Ag/Pd nanoparticles

It is shown that both the growth and shrinkage of hollow shells in Ag/Pd hemispherical core-shell nanostructures take place at the same temperature. The crossover time, t _cr, between these regimes is shifted to lower values with increasing temperature. This result confirms that the growth and shrinkage regimes are controlled by the faster and slower diffusion coefficients (D _Ag and Ds _Pd), respectively. The pore radius, confirming recent theoretical predictions, linearly depends on the initial particle radius, and the slope of this straight line increases with the average composition of the faster component.