AuPd Bimetallic Nanocrystals Embedded in Magnetic Halloysite Nanotubes: Facile Synthesis and Catalytic Reduction of Nitroaromatic Compounds.

Lei Jia,Beibei Zhang,Shengli Guo,Jun Xu,Xiaoke Shen,Tao Zhou,Fenghai Li,Wensheng Zhang,Zhouqing Xu

doi:10.3390/nano7100333

Abstract

In this research, a facile and effective approach was developed for the preparation of well-designed AuPd alloyed catalysts supported on magnetic halloysite nanotubes (HNTs@Fe3O4@AuPd). The microstructure and the magnetic properties of HNTs@Fe3O4@AuPd were confirmed by transmission electron microscopy (TEM), high resolution TEM (HRTEM), energy-dispersive X-ray spectroscopy (EDS), and vibrating sample magnetometry (VSM) analyses. The catalysts, fabricated by a cheap, environmentally friendly, and simple surfactant-free formation process, exhibited high activities during the reduction of 4-nitrophenol and various other nitroaromatic compounds. Moreover, the catalytic activities of the HNTs@Fe3O4@AuPd nanocatalysts were tunable via adjusting the atomic ratio of AuPd during the synthesis. As compared with the monometallic nanocatalysts (HNTs@Fe3O4@Au and HNTs@Fe3O4@Pd), the bimetallic alloyed HNTs@Fe3O4@AuPd nanocatalysts exhibited excellent catalytic activities toward the reduction of 4-nitrophenol (4-NP) to 4-aminophenol. Furthermore, the as-obtained HNTs@Fe3O4@AuPd can be recycled several times, while retaining its functionality due to the stability and magnetic separation property.

Highlights

Noble metal nanoparticles (NPs), owing to their remarkable chemical and physical properties, have attracted significant attention in recent decades due to their potential use in electronics [1], optical devices [2], fuel cells [3], chemical sensors [4], catalysis [5,6,7] and biological materials [8,9,10]
An AuPd–MnOx/ZIF-8–rGO nanocatalyst prepared by a facile wet-chemical strategy showed highly efficient catalytic activity in the additive free dehydrogenation of formic acid [19]
We reported a facile and convenient method to prepare the magnetic recoverable nanocatalysts Halloysite nanotubes (HNTs)@Fe3O4@AuPd

Summary

Introduction

Noble metal nanoparticles (NPs), owing to their remarkable chemical and physical properties, have attracted significant attention in recent decades due to their potential use in electronics [1], optical devices [2], fuel cells [3], chemical sensors [4], catalysis [5,6,7] and biological materials [8,9,10] Among these metals, gold nanoparticles (Au NPs) are frequently used for various catalytic reactions because Au catalyst is completely stable and active under mild condition [11,12]. The magnetic HNTs@Fe3O4 were further modified by the AuPd alloyed NPs or monometallic Au or Pd NPs. The catalytic activities of the above nanocatalysts toward the reduction reaction of 4-NP and its derivative in the presence of NaBH4 were investigated. Tthhaencothnrveeersmioonnotfh4s.-NTPhewcaosnsvimerisliaornafotfer4t-hNePcawtaalsysstismairlearpareftpearrethdethcraetealmysotsntahrse later, suggesting that the catalysts were stable and can be used within three months without an obvious loss of activity [59]

Materials

Catalytic Reduction of Nitrobenzene

Characterization

Conclusions