Synthesis, Characterization, and Mechanism of Formation of Janus-Like Nanoparticles of Tantalum Silicide-Silicon (TaSi2/Si)

Abstract

Metal-semiconductor Janus-like nanoparticles with the composition tantalum silicide-silicon (TaSi2/Si) were synthesized for the first time by means of an evaporation method utilizing a high-power electron beam. The composition of the synthesized particles were characterized using high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), selective area electron diffraction (SAED), and energy dispersive X-ray fluorescence (EDX) analysis. The system is compared to previously synthesized core-shell type particles in order to show possible differences responsible for the Janus-like structure forming instead of a core-shell architecture. It is proposed that the production of Janus-like as opposed to core-shell or monophase particles occurs due to the ability of Ta and Si to form compounds and the relative content of Ta and Si atoms in the produced vapour. Based on the results, a potential mechanism of formation for the TaSi2/Si nanoparticles is discussed.

Structural Evolution and Electronic Properties of TaSin–/0 (n = 2–15) Clusters: Size-Selected Anion Photoelectron Spectroscopy and Theoretical Calculations

“…Numerous vapor deposition experiments combined with theoretical calculations suggested that Ta@Si 16 + or Ta@Si 16 nanoclusters can retain their cagelike geometries and charge states when they are deposited on the conductive C 60 and graphite substrates. − M@Si 16 (M = Ti and Ta) superatomic nanoclusters have been synthesized using the dry–wet combination synthesis method, and further studies indicated that they adopt metal-encapsulating tetrahedral silicon-cage geometries with closed-shell electronic configuration. , The reaction of nitric oxide (NO) with Ta@Si 16 superatom deposited on the overlayered C 60 substrates was investigated by X-ray photoelectron spectroscopy in conjunction with density functional theory (DFT) calculations, and the results showed that NO can only be oxidized by the exposed Ta atom . Recently, Janus-like TaSi 2 /Si nanoparticles were synthesized . In this work, in order to measure the photoelectron spectra of TaSi n – clusters with better resolution and to explore the structural evolution and electronic properties of TaSi n clusters, we studied the TaSi n –/0 ( n = 2–15) clusters by means of size-selected anion photoelectron spectroscopy and quantum chemical calculations.…”

“…34 Recently, Janus-like TaSi Si nanoparticles were synthesized. 35 In this work, in order to measure the photoelectron spectra of TaSi n − clusters with better resolution and to explore the structural evolution and electronic properties of TaSi n clusters, we studied the TaSi n −/0 (n = 2−15) clusters by means of size-selected anion photoelectron spectroscopy and quantum chemical calculations.…”

Formation of metal/semiconductor Cu–Si composite nanostructures

“…The structure of these nanoparticles is primarily determined by the methods and conditions of synthesis, which should allow us to combine the two materials even if they are immiscible in the bulk state. In addition to chemical techniques [9][10][11][12], physical methods such as gas-phase methods [5,6,15], laser ablation [7,8,16], and magnetron-sputter gas-phase condensation [17] have been developed. When these methods are combined with the possibility of rapid heating and evaporation of both materials and the possibility of rapid controlled cooling of the resulting vapour mixture, the formation of nanoparticles with a complex structure is possible.…”

Composite Nanoparticles: Getting Under the Irradiation of the Electron Beam, Modeling of Processes of Formation of Molecular-Dynamic Method

“…Янус-подобные наночастицы металл/полупроводник являются перспективными в качестве эффективных радиопоглощающих сред и основой для создания элементной базы для СВЧ электроники и радиофотоники вследствие наличия у них большого дипольного момента. В работах авторов [5][6][7][8] представлен механизм образования наночастиц ядрооболочка и янус-подобных основанный на разнице поверхностных энергий составляющих частицу компонентов и термодинамического анализа двухкомпо-нентных фазовых диаграмм. Однако, механизм образования не учитывает неравновесность процессов образования наночастиц созданных методом газофазного синтеза, поэтому остаются неясными вопросы влияния на их образование, структуру, морфологию кинетических характеристик: скорости охлаждения, времени нахождения в жидкой фазе.…”