FePt nanodendrites with high-index facets as active electrocatalysts for oxygen reduction reaction

Self‐Assembled Dendritic Pt Nanostructure with High‐Index Facets as Highly Active and Durable Electrocatalyst for Oxygen Reduction

“…Fourier-transformed pattern (Figure 2d)a lso revealed the presenceo fh igh-index {311} facets in Pt nanodendrites, which is one of the most active and stable Pt surfacestructures for the ORR. [57,58,60] To clearly investigate the microscopics tructure of Pt nanodendrites,C Oo xidation measurements were conducted as shown in Figure 3. The CO oxidationa nalysis is an important technique to identify particle surface structures, and provides af ingerprint of the extent of particlea gglomeration and the existence of high-index facets on nanocrystals.…”

“…[76] After desorption of O atomsf rom the surface at lower potential, those relocatedP t atomsc annot return to their originalp ositions, so the ordered surfaces tructure will be destroyed during as evere potential cycling test resulting in performance degradation for the ORR. [60] Consequently, it is supposed that Pt nanodendrites could retain the originals urfacen anostructure during1 0000 potential cycles owing to the formation of well-organized dendritic Pt nanostructures with intrinsically stable high-index surfaces in the high-potential region. [60] Consequently, it is supposed that Pt nanodendrites could retain the originals urfacen anostructure during1 0000 potential cycles owing to the formation of well-organized dendritic Pt nanostructures with intrinsically stable high-index surfaces in the high-potential region.…”

“…In contrast, on the Pt surfaces enclosed by high-index facets, the Oa toms preferentially adsorb without changing the position of Pt atomse ven at high potentials, so the ordereds urfaces are preserved. [60] Consequently, it is supposed that Pt nanodendrites could retain the originals urfacen anostructure during1 0000 potential cycles owing to the formation of well-organized dendritic Pt nanostructures with intrinsically stable high-index surfaces in the high-potential region. [53][54][55][56]58] In addition, this suggests that the control of the crystallographic facets and particle structure of nanocatalysts has as ignificant effect on the catalytic activity and durability.…”

“…[53][54][55][56]58] Therefore, nanocrystals with high-index facets exhibited impressive catalytic activity and durability for ORR. [59,60] More carefulf abricationp rocedures are required to make Pt nanoparticles,n ot alloy particles, with high-index facets, for example, an electrochemical square-wave potentialc ycling method. Nanocrystal structuresw ith high-index facets have been recently explored to solve the critical durability problem of fuel cell catalysts as Pt catalysts with high-index facets can preserve the ordered surfaces without change of the originals tructures.…”

“…[57] FePt nanodendrites are fabricated by applying ap ost-treatments uch as galvanic replacement or cation-exchange reactionb etween Fe and Pt 4 + on the surface of Fe nanoparticles. [59,60] More carefulf abricationp rocedures are required to make Pt nanoparticles,n ot alloy particles, with high-index facets, for example, an electrochemical square-wave potentialc ycling method. [53,54] Therefore, the development of facile synthesis of Pt-basedn anostructures with high-index facets is still challenging.…”