Pulsed laser irradiation of colloidal nanoparticles: a new synthesis route for the production of non-equilibrium bimetallic alloy submicrometer spheres

Abstract

A new one-step approach was developed to synthesize bimetallic alloy submicrometer spheres, which are immiscible under equilibrium, using AuCo as a model system. Uniform, single-phase AuCo alloy submicrometer particles (y230 nm) with a welldefined spherical morphology were successfully formed via pulsed laser irradiation of Au and Co-oxides nanoparticles dispersed in ethanol and characterized with a combination of electron microscopy, diffraction and magnetization measurements.

Laser‐Irradiation‐Induced Melting and Reduction Reaction for the Formation of Pt‐Based Bimetallic Alloy Particles in Liquids

“…According to alloying compositions, the preparations of noble-metal-based bimetallic alloys by LML could be classified into two categories:n oble metal-noble metal (NM-NM)a lloys, such as Au-Ag, [28] Pt-Au, [29] Ag-Pd, [30] and noble metal-transition metal (NM-TM) alloys, such as Au-Co. [31] Generally,f or preparing NM-NM alloys, pure noble-metal NPs were used as reactionp recursors. ratio, crystalline phase, and size distribution of the bimetallic alloys were determined by the reaction precursors, type of liquid, laser fluence, and irradiationt ime.…”

“…According to alloying compositions, the preparations of noble-metal-based bimetallic alloys by LML could be classified into two categories:n oble metal-noble metal (NM-NM)a lloys, such as Au-Ag, [28] Pt-Au, [29] Ag-Pd, [30] and noble metal-transition metal (NM-TM) alloys, such as Au-Co. [31] Generally,f or preparing NM-NM alloys, pure noble-metal NPs were used as reactionp recursors. For instance, Swiatkowska-Warkocka [31] prepared Au-Co colloids through pulsed laser irradiation of Au and Co-oxides NPs dispersed in ethanol. Chen [25] synthesized Au-Ag alloy NPs by laser irradiationo fm ixtures consisting of Au and Ag NPs originated from aw et-chemical method.…”

“…ratio, crystalline phase, and size distribution of the bimetallic alloys were determined by the reaction precursors, type of liquid, laser fluence, and irradiationt ime. According to alloying compositions, the preparations of noble-metal-based bimetallic alloys by LML could be classified into two categories:n oble metal-noble metal (NM-NM)a lloys, such as Au-Ag, [28] Pt-Au, [29] Ag-Pd, [30] and noble metal-transition metal (NM-TM) alloys, such as Au-Co. [31] Generally,f or preparing NM-NM alloys, pure noble-metal NPs were used as reactionp recursors. For example, Mafun [29] prepared Pt-Au alloy NPs by post-irradiationo f Pt and Au colloidsderived from laser ablation of Pt and Au targets in liquids.…”

“…In contrast, to obtain NM-TM alloys, transition-metal oxidesh ave typically been used as precursors but not pure transition metals. For instance, Swiatkowska-Warkocka [31] prepared Au-Co colloids through pulsed laser irradiation of Au and Co-oxides NPs dispersed in ethanol.…”

Inclusion of supported gold nanoparticles into their semiconductor support

“…At a fluence of 150 mJ/cm² the SMS showed a rough surface. Additionally, PLML-alloying of non-equilibrium phases is known 22 . The influence of educt particle size on melting effectivity was demonstrated by Tsuji et al 12 .…”