“…The nanowirelike backbones are derived from the fusion and connection of the particulate NBBs (mostly noble metal NPs) during the gelation process. Depending on the elemental composition and distribution, these aerogels can be divided into three types: monometallic aerogels (Pd, Pt, Au, Ag), [38,39,46,47] bimetallic alloy aerogels (Pd x Pt y , Pt x Ni, Pt x Cu, etc), [25,26,49] and mixed multi/bimetallic aerogels (Au-Pd, Pd-Pt, Au-Ag-Pt, etc.). [45,50] Figure 2 shows the representative scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images of the wire-based aerogels.…”