Micelle-mediated UV-photoactivation route for the evolution of Pdcore–Aushell and Pdcore–Agshell bimetallics from photogenerated Pd nanoparticles

Bimetallic Au-Pd nanoparticles supported on silica with a tunable core@shell structure: enhanced catalytic activity of Pd(core)-Au(shell) over Au(core)-Pd(shell)

A facile ligand-assisted approach of synthesizing bimetallic Au-Pd nanoparticles supported on silica with a tunable core@shell structure is presented. Maneuvering the addition sequence of metal salts, both Aucore-Pdshell (Au@Pd-SiO2) and Pdcore-Aushell (Pd@Au-SiO2) nanoparticles were synthesized. The structures and compositions of the core-shell materials were confirmed by probe-corrected HRTEM, TEM-EDX mapping, EDS line scanning, XPS, PXRD, BET, FE-SEM-EDX and ICP analysis. The synergistic potentials of the core-shell materials were evaluated for two important reactions viz. hydrogenation of nitroarenes to anilines and hydration of nitriles to amides. In fact, in both the reactions, the Au-Pd materials exhibited superior performance over monometallic Au or Pd counterparts. Notably, among the two bimetallic materials, the one with Pdcore-Aushell structure displayed superior activity over the Aucore-Pdshell structure which could be attributed to the higher stability and uniform Au-Pd bimetallic interfaces in the former compared to the latter. Apart from enhanced synergism, high chemoselectivity in hydrogenation, wide functional group tolerance, high recyclability, etc. are other advantages of our system. A kinetic study has also been performed for the nitrile hydration reaction which demonstrates first order kinetics. Evaluation of rate constants along with a brief investigation on the Hammett parameters has also been presented.

Green synthesis of the Cu/ZnO nanoparticles mediated by Euphorbia prolifera leaf extract and investigation of their catalytic activity

A green synthesis process was developed for the preparation of the Cu/ZnO nanoparticles (NPs) using Euphorbia prolifera leaf extract as a mild, renewable and non-toxic reducing agent and efficient stabilizer without using dangerous, hazardous and toxic materials. The approach of biosynthesis appears to be cost efficient eco-friendly and easy alternative to conventional methods of the Cu/ZnO NPs synthesis. The Cu/ZnO NPs were characterized by FESEM, EDS, elemental mapping, TEM and XRD. TEM micrograph has shown the formation of Cu NPs with the size in the range of 5-17 nm. In addition, the synthesized Cu/ZnO NPs presented excellent catalytic activity for the degradation of Methylene blue (MB) and Congo red (CR) in the presence of NaBH4 in water at room temperature.

Asymmetric Au-core Pd-shell nanoparticles supported on reduced graphene oxide for enhanced electrocatalytic activity

Asymmetric Au-core Pd-shell nanoparticles supported on rGO simply prepared by a GRR-like technique exhibit superior ORR performance compared to commercial Pt/C.

Mg2+-assisted low temperature reduction of alloyed AuPd/C: an efficient catalyst for hydrogen generation from formic acid at room temperature

An alloyed AuPd/C nanocatalyst was prepared via Mg²⁺-assisted low temperature reduction, and exhibited high activity in room temperature decomposition of formic acid.

Methods and strategies for the synthesis of diverse nanoparticles and their applications: a comprehensive overview

Various methods to synthesize diverse nanoparticles with their different applications.

Ligand-stabilized metal nanoparticles in organic solvent

This critical review reports the fundamental behavior of metal nanoparticles in different organic solvents, i.e., metal organosol. An overview on metal organosol and then their smart synthetic approaches, characterization, and potential applications in the fields of catalysis and spectroscopy with special emphasis on SERS are embodied. Aspects of organosol fabrication, stabilization, morphology control, growth mechanisms, and physical properties as mono- and bimetallic nanoparticles are discussed. The article inspires the repetitive usage of metal nanoparticles as stable deliverable organic and molecular compounds.

A Simple Method for Measuring the Size of Metal Nanoclusters in Solution

The connection between quantum size effects and the surface plasmon resonance of metal nanoclusters is introduced and the pros and cons of in situ and ex situ cluster analysis methods are outlined. A new method for estimating the size of nanoclusters is presented. This method combines core/shell cluster synthesis, UV-visible spectroscopy, and Mie theory. The core/shell approach enables the estimation of metal cluster sizes directly from the UV-visible spectra, even for transition metal nanoclusters such as Pd that have no distinct surface-plasmon peak in UV-visible region. Pd/Au and Au/Pd core/shell clusters as well as Au-Pd alloy clusters are synthesized and used as test cases for simulations and spectroscopic measurements. The results of the simulations and UV-visible spectroscopy experiments are validated with transmission electron microscopy.

Synthesis and characterization of N,N-dimethyldodecylamine-capped Aucore-Pdshell nanoparticles in toluene

In this paper a convenient route for synthesizing Au(core)-Pd(shell) bimetallic nanoparticles in toluene has been reported as a result of co-reduction of gold(III) and palladium(II) precursors in toluene. N,N-Dimethyldodecylamine was used as a capping agent for the core-shell particles, which not only imparts stability to the organosol but also controls morphology of the evolved particles. The particles were characterized using UV-visible, transmission electron microscopy, and X-ray diffraction measurements. All results substantiate the formation of core-shell structure of the synthesized particles.