Core@shell, Au@TiO_xnanoparticles by gas phase synthesis

Abstract

Herein, gas phase synthesis and characterization of multifunctional core@shell, Au@TiO x nanoparticles have been reported. The nanoparticles were produced via a one-step process using a multiple-ion cluster source under a controlled environment that guaranteed the purity of the nanoparticles. The growth of the Au cores (6 nm diameter) is stopped when they pass through the Ti plasma where they are covered by an ultra-thin (1 nm thick) and homogeneous titanium shell that is oxidized in-flight before the soft-landing of the nanoparticles. The Au cores were found to be highly crystalline with icosahedral (44%) and decahedral (66%) structures, whereas the shell, mainly composed of TiO 2 (79%), was not ordered. The highly electrical insulating behaviour of the titanium oxide shell was confirmed by the charging effect produced during X-ray photoemission spectroscopy.

Physical Synthesis and Study of Ag@CaF2 Core@Shell Nanoparticles: Morphology and Tuning of Optical Properties

“…For instance, it was possible to study systematically the effect of non‐native oxide shell thickness and composition on the magnetic and structure properties of Ni@NiO, Ni@CoO, Ni@MgO, and FePt@MgO NP assemblies . In recent papers, complex core@shell and core@shell@shell NPs were obtained by modified gas aggregation sources, similar to the one used in the present work and in previous studies …”

Gas-phase synthesis of nanoparticles: present status and perspectives

“…The magnetrons are completely independent regarding their power supply and argon feed but most importantly that can be placed at different positions in the aggregation zone in an independent manner. Such design has been called Multiple Ion Cluster Source (MICS) as it has multiple magnetrons and it has been proven to be very powerful and flexible for the formation of alloyed nanoparticles with well-controlled chemical composition and size [10] and also for the engineering of core@shell and core@shell@shell nanoparticles [11,12,13]. Figure 1 illustrates the different configurations that are used for the synthesis of the variety of nanoparticles.…”

Electrocatalytic Behavior of PtCu Clusters Produced by Nanoparticle Beam Deposition

“…The sputtering power, Ar gas flux, and condensation length (distance between the target and the exit nozzle) for each magnetron were controlled separately. 27 , 28 The relative Pt content of the PtCu clusters produced lay in the range 2–38 at. %.…”