Nickel platinum (Ni_xPt_1−x) nanoalloy monodisperse particles without the core–shell structure by colloidal synthesis

Abstract

<p>We report a new and versatile colloidal route towards the synthesis of nanoalloys with controlled size and chemical composition in the solid solution phase (without such phases segregations as core-shell...</p>

Light‐Driven Alcohol Splitting by Heterogeneous Photocatalysis: Recent Advances, Mechanism and Prospects

“…For example, structures and properties of the co‐catalysts determine both the hydrogen evolution reaction and the possible side‐reactions. It has been well‐known that different kinds of metals can form solid solutions, [115,134,152] intermetallic compounds, [127,133,134,153,154] and versatile nanostructures (e. g. core‐shell structures) [31,134,155] . Investigating structures of the co‐catalysts as well as the metal/semiconductor interfaces on the atomic level utilizing spherical‐aberration‐corrected TEM and scanning TEM (STEM) will certainly create more exciting results.…”

Colloidal synthesis of nanoparticles: from bimetallic to high entropy alloys

“…37 Using this colloidal route, bimetallic nickel–platinum NPs have been recently obtained with a specific controlled chemical composition, ranging from pure Ni to pure Pt and a well-defined size below 5 nm. 30 More precisely, the synthesis temperature proved to be crucial to produce NPs in the solid solution phase, i.e. without phase segregation such as core–shell or Janus structures.…”

“…Indeed, if one element reduces before the others, it will be the first to nucleate giving rise to core–shell structures. As highlighted in the case of bimetallic Ni x Pt 1− x NPs, 30 the key point to obtain solid solution NPs is to compensate the differences in the reactivities of the metallic precursors by increasing the temperature of the synthesis. We established a linear correlation between the difference in the standard redox potentials of the cations used and the temperature required to obtain bimetallic solid solution nanoalloys.…”

“…We established a linear correlation between the difference in the standard redox potentials of the cations used and the temperature required to obtain bimetallic solid solution nanoalloys. 30 The synthesis is therefore carried out at a suitable temperature which ensures that all metal precursors are reduced at the same rate. To sustain this temperature, we have developed a hot injection technique where a combined solution of metal precursors and a reducing agent contained in a minimum volume of solvent is rapidly injected into a much larger volume of hot solvent containing surface stabilizing agents.…”

“…To achieve this goal, we extend our new colloidal route to the synthesis of bimetallic Ni x Pt 1− x with controlled size and chemical composition to fabricate HEA NPs. 30 A major difficulty in the optimization of the synthesis parameters is to characterise the obtained NPs. Typically, X-Ray diffraction (XRD) analyses can be used but in case of small NPs, very broad and low intensity peaks are observed 23 making the analysis difficult for elements with the same crystallographic structure and close lattice parameters as discussed in the present work.…”