Synthesis of Free‐Standing Pd‐Ni‐P Metallic Glass Nanoparticles with Durable Medium‐Range Ordered Structure for Enhanced Electrocatalytic Properties

Abstract

Topologically disordered metallic glass nanoparticles (MGNPs) with highly active and tailorable surface chemistries have immense potential for functional uses. The synthesis of free‐standing MGNPs is crucial and intensively pursued because their activity strongly depends on their exposed surfaces. Herein, a novel laser‐evaporated inert‐gas condensation method is designed and successfully developed for synthesizing free‐standing MGNPs without substrates or capping agents, which is implemented via pulse laser‐induced atomic vapor deposition under an inert helium atmosphere. In this way, the metallic atoms vaporized from the targets collide with helium atoms and then condense into short‐range‐order (SRO) clusters, which mutually assemble to form the MGNPs. Using this method, free‐standing Pd40Ni40P20 MGNPs with a spherical morphology are synthesized, which demonstrates satisfactory electrocatalytic activity and durability in oxygen reduction reactions. Moreover, local structure investigations using synchrotron pair distribution function techniques reveal the transformation of SRO cluster connection motifs of the MGNPs from face‐sharing to edge‐sharing modes during cyclic voltammetry cycles, which enhances the electrochemical stability by blocking crystallization. This approach provides a general strategy for preparing free‐standing MGNPs with high surface activities, which may have widespread functional applications.

Applications of amorphous inorganics as novel functional materials

“…57 For instance, Lan and colleagues discovered that amorphous Pd–Ni–P metallic glass nanoparticles (MGNP) performed an MRO rearrangement against harmful crystallization during long-term CV cycles. 58 The MGNP could transform between two- to three-atom modes at MRO, plays a crucial role in stabilizing its amorphous state and prevents crystalline-induced degradation.…”