Directional coalescence growth of ultralong Au₉₃Pt₇ alloy nanowires and their superior electrocatalytic performance in ethanol oxidation

Abstract

Ultralong (∼25-30 μm) surface-Pt-rich Au93Pt7 alloy nanowires (ANWs) were achieved by a directional coalescence between spherical nanoparticles. Also, the ANWs exhibit superior electrocatalytic activity and long-term durability towards ethanol oxidation, ∼12 times in the mass activity better than the state-of-the-art commercial Pt/C catalyst.

Serrated Au/Pd Core/Shell Nanowires with Jagged Edges for Boosting Liquid Fuel Electrooxidation

“…However, in the final Au 36 Pd 64 CSNWs, we did not find noticeablee nrichment of Pd in the inner Au core to support this assumption, and AuPt nanowires were also produced without Pd precursorsb yd irectional coalescence. [26] EDX-element mapping analysis( Figure S4) further confirmedt he occurrence of co-reduction of Pd II and Au I :b oth Au and Pd species were shown to be distributed relatively evenly in the nanorods, suggesting that the product at this stage is an alloy.A t1 0min, nanowires began to appear and had relatively smooth surfaces (FigureS2e). EDX-element mapping images ( Figure S5) disclosedt hat the Pd content gradually increased from the inner to the outside locations and tended to accumulate at the periphery.H owever,s pontaneous phase segregation cannot happena t3 08C.…”

“…This nanowire growth mode cannot be attributed to the orientated attachment because of the existence of Moiré fringes and the mismatch of lattice fringes except for the straight segment (Figure S3). We called this growth mode “directional coalescence” . Krichevski and Markovich presumed that the pre‐reduced Pd 0 acted as a binder to connect Au nanoparticles to produce nanowires.…”

“…Krichevski and Markovich presumed that the pre‐reduced Pd 0 acted as a binder to connect Au nanoparticles to produce nanowires. However, in the final Au 36 Pd 64 CSNWs, we did not find noticeable enrichment of Pd in the inner Au core to support this assumption, and AuPt nanowires were also produced without Pd precursors by directional coalescence . EDX‐element mapping analysis (Figure S4) further confirmed the occurrence of co‐reduction of Pd II and Au I : both Au and Pd species were shown to be distributed relatively evenly in the nanorods, suggesting that the product at this stage is an alloy.…”

“…W ec alled this growth mode "directional coalescence". [26] Krichevski and Markovich [24] presumed that the pre-reduced Pd 0 acted as ab inder to connect Au nanoparticles to produce nanowires. However, in the final Au 36 Pd 64 CSNWs, we did not find noticeablee nrichment of Pd in the inner Au core to support this assumption, and AuPt nanowires were also produced without Pd precursorsb yd irectional coalescence.…”

Nanocatalysts for Electrocatalytic Oxidation of Ethanol

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