Synthesis of AuPd alloyed nanoparticles via room-temperature electron reduction with argon glow discharge as electron source.

Manman Yang,Zongyuan Wang,Wei Wang,Chang-Jun Liu

doi:10.1186/1556-276x-9-405

Abstract

Argon glow discharge has been employed as a cheap, environmentally friendly, and convenient electron source for simultaneous reduction of HAuCl4 and PdCl2 on the anodic aluminum oxide (AAO) substrate. The thermal imaging confirms that the synthesis is operated at room temperature. The reduction is conducted with a short time (30 min) under the pressure of approximately 100 Pa. This room-temperature electron reduction operates in a dry way and requires neither hydrogen nor extra heating nor chemical reducing agent. The analyses using X-ray photoelectron spectroscopy (XPS) confirm all the metallic ions have been reduced. The characterization with X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) shows that AuPd alloyed nanoparticles are formed. There also exist some highly dispersed Au and Pd monometallic particles that cannot be detected by XRD and transmission electron microscopy (TEM) because of their small particle sizes. The observed AuPd alloyed nanoparticles are spherical with an average size of 14 nm. No core-shell structure can be observed. The room-temperature electron reduction can be operated in a larger scale. It is an easy way for the synthesis of AuPd alloyed nanoparticles.

Highlights

Alloyed AuPd bimetallic nanoparticles have drawn great attention because of their unique properties for optical, electronic, magnetic, and catalytic applications [1,2,3]
The X-ray diffraction (XRD) patterns of AuPd-anodic aluminum oxide (AAO) show a big peak at 38.54°, which is between pure Au (111) plane (38.184°; PDF# 04-0784) and pure Pd (111) plane (40.118°; PDF# 46-1043)
These results suggest that alloyed bimetallic nanoparticles are formed over AuPd-AAO [4]

Summary

Introduction

Alloyed AuPd bimetallic nanoparticles have drawn great attention because of their unique properties for optical, electronic, magnetic, and catalytic applications [1,2,3]. A variety of approaches have been reported on the preparation of alloyed AuPd nanoparticles, including chemical reduction [3,4,5], electrochemical reduction [1,6], thermolysis of double metallic salts [2], and sonochemical reduction [7]. Among all these methods, the chemical reduction is mostly applied. Mariotti and Sankaran [14] and Yan et al [15] reported a microplasma reduction for synthesis of alloyed nanoparticles at atmospheric pressure. These represented a remarkable progress in the green and energy-efficient synthesis of alloyed nanoparticles

Methods

Results

Conclusion