Kinetically Controlled Direct Synthesis of B2- and A1-Structured Cu–Pd Nanoparticles

Abstract

Atomic arrangement in Cu−Pd alloy nanoparticles (NPs) has been reported to influence the catalytic activity, but they have yet to be studied in detail. Unlike previous studies, where the B2 structure Cu−Pd NPs are obtained by heat treating the A1 structure, this study reports the one-pot direct syntheses of A1-and B2structured Cu−Pd NPs using an alcohol reduction method. The alcohol reduction technique facilitates the kinetic control of the reduction reaction by selecting the appropriate alcohol type and complexing agent to delay the reduction of easily reducible metallic elements to realize control over the reduction kinetics for coreduction. Different formation mechanisms for A1-and B2-structured CuPd NPs were confirmed by in situ ultraviolet−visible (UV−vis) measurements and morphological and structural analyses of samples withdrawn during the reaction. Finally, the direct formation of single-phase B2-structured Cu−Pd NPs with an average diameter of 18.6 ± 7.6 nm was realized using tri-n-octyl phosphine as a complexing agent. The noticeable crystal structural dependence of the electrocatalytic CO 2 reduction reaction properties of A1-and B2structured CuPd NPs was demonstrated.

Synthesis of low-cost multi-element Pt-based alloy nanoparticles as catalysts for the oxygen reduction reaction

“…These factors have been considered for the synthesis of bimetallic Ni–Pt, Cu–Ni, Co–Ni, Co–Pt, and Cu–Pd nanostructures using long alkyl chain alcohols as reducing agents. 36,37,59–65…”

“…The advantage of this method is its ability to not only reduce the low redox potential of transition metal elements such as Cu, Co, or Ni, 59,67,68 but also to accommodate other phenomena such as diffusion, etching, and galvanic substitution reactions to facilitate the synthesis of bimetallic nanostructures with controlled morphology, composition, and elemental distribution. 36,37,59–65 Therefore, the synthesis of NiPtPd alloy NPs with controllable composition and elemental distribution is attempted, focussing on the above two points. Furthermore, the catalytic performance of Ni 78 Pt 11 Pd 11 alloy NPs/C electrodes compared with Ni 74 Pt 26 NPs and commercial Pt in the ORR is also reported.…”