2014 Volume 55 Issue 5 Pages 796-800
The micro-alloying of 1 at% metals of Au-Group (Ag, Au) and the Pt-Group (Ni, Pd, Pt) with the Ti60Cu40 amorphous alloy resulted in the formation of fine nanoporous copper (NPC) in the order of 6–28 nm. The smallest characteristic pore size of open–cell nanoporous fcc Cu was 7 and 6 nm after dealloying the amorphous Ti60Cu39Pd1 and Ti60Cu39Pt1 precursor alloys for 43.2 ks in 0.03 M HF solution, while NPC had a pore size of 39 nm after dealloying the amorphous Ti60Cu40 precursor alloy. On the basis of TEM micrographs, the refining factor increased approximately from 4 for the Ti60Cu39Ag1 precursor alloy to 1780 for the Ti60Cu39Pt1 precursor alloy. The refinement was attributed to the dramatic decrease in the surface diffusivity during dealloying. The refinement efficiency of the micro-alloying of the Pt-group elements was higher than that of the Au-group elements. The homogeneous distribution of additives in both of the amorphous precursor alloys and the final stabilized NPCs played a key role in refining the NPCs. This strategy may contribute to the fabrication of cost-effective nanoporous metals with a nanoporosity comparable to that of nanoporous Au, Pd and Pt catalysts.