Synthesis, Microstructure, and Catalytic Performance of Monolithic Low‐Density Porous Au

Abstract

A series of monolithic porous Au with different pore sizes are successfully synthesized by a facile template-dealloying corrosion method. Spherical Cu particles are employed as sacrificial templates, and a FeCl 3 -HNO 3 two-step corrosion method is developed to dissolve the Cu components. The microstructure and phase evolution, as well as the effect of the corrosive media, are investigated in this study. As a result, the prepared monolithic porous Au possesses ultra-low density and a special hollow porous core-shell structure. When a small-sized template (%1 mm) is adopted, the corresponding density is as low as 0.37 g cm À3 (1.8% of the full density of Au). In addition, due to the special structure, the monolithic porous Au exhibits good catalytic performance (K app ¼ 0.43 min À1 ), that is, relatively higher than that of most traditional Au-based powder/slurry materials.

Ultrastable Plasmonic Cu-Based Core–Shell Nanoparticles

“…However, the Cu nanowires can still be etched by acetic acid, perhaps due to the imperfect thin-shell coverage. In another study, a porous Au shell was synthesized through a dealloying approach, where the Cu core can be easily etched by HNO 3 . Thus, a complete, compact, stable thin shell is needed to obtain highly stable Cu NPs, resisting oxidation and acids.…”