A general dealloying route to synthesize nanoporous non-noble metals

At present, most studies focus upon the synthesis of nanoporous noble metals such as Au, Ag, Pt and Pd. Here we show that the dealloying route can be generally used to fabricate nanoporous non-noble metals like Bi, Ga and Sn, and rapidly solidified Mg-based (Mg-Bi, Mg-Ga and Mg-Sn) precursors were utilized. The microstructure of the as-obtained nanoporous metals has been characterized using X-ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis. These nanoporous metals show a three-dimensional bicontinuous ligament-channel structure. It has been found that the more active Mg atoms were selectively etched away during dealloying, and the residual elements (Bi, Ga and Sn) diffused and agglomerated to form the nanoporous structure.