Synthesis of Cu₃Sn Alloy Nanocrystals through Sequential Reduction Induced by Gradual Increase of the Reaction Temperature

Abstract

Cu3Sn alloy nanocrystals are synthesized by sequential reduction of Cu and Sn precursors through a gradual increase of the reaction temperature. By transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), UV/Vis spectroscopy, and X-ray diffraction (XRD) analyses, the alloy formation mechanism of Cu3Sn nanocrystals has been studied. The incremental increase of the reaction temperature sequentially induces the reduction of Sn, the diffusion of Sn into the preformed Cu nanocrystals, resulting in the intermediate phase of Cu-Sn alloy nanocrystals, and then the formation of Cu3Sn alloy nanocrystals. We anticipate that the synthesis of Cu3Sn alloy nanocrystals encourages studies toward the synthesis of various alloy nanomaterials.

Smart Solution Chemistry to Sn‐Containing Intermetallic Compounds through a Self‐Disproportionation Process

“…If continuously increasing n CuCl 2 ⋅ 2 H 2 O to 10 mmol (line f), impurity of metallic Cu increased. Previous study on the evolution of Cu 6 Sn 5 to Cu 3 Sn is basically dependent on the control of temperature or aging time: lower temperature tends to form Cu 6 Sn 5 , whereas a higher temperature is more likely to produce Cu 3 Sn . If the temperature remains unchanged, Cu 6 Sn 5 is initially formed and then comes to Cu 3 Sn, because Cu 6 Sn 5 grows much faster than Cu 3 Sn .…”

“…processes . With these synthetic routes, well‐defined monodisperse Sn−Cu, Pt 3 Sn, and Sn−Sb, etc., nano‐intermetallic compounds have been synthesized successfully. Unfortunately, an important restriction on the fabrication of monodisperse particles lies in the strict condition and utilization of toxic organic capping agents, solvents, reducing agents, and organo‐metals.…”

Application of Low-Cost Cu–Sn Bimetal Alloy as Oxygen Reduction Reaction Catalyst for Improving Performance of the Microbial Fuel Cell

“…In addition to the desired alloy, few more diffraction peaks at 2θ = 43.2 o , 50.4 o and 74.1 o were noticeable, which can be indexed as cubic symmetry of pure Cu element (#JCPDS card 04-0836). The presence of Cu element can be attributed to the early formation of Cu during the thermal reduction as the Cu 2+ has high positive reduction potential of 0.34 V [12]. In addition, possibility of SnO formation was also analysed; the reference peak positions as shown in the Figure 1b, for pure SnO tetragonal symmetry (#JCPDS card 072-1012) did not match with the XRD pattern of as-synthesised material, confirming absence SnO in the material.…”

Robust Cu–Cu Bonding with Multiscale Coralloid Nano-Cu3Sn Paste for High-Power Electronics Packaging

“…However, there is no report about the direct Cu–Cu bonding using the nano-Cu 3 Sn/PEG-400 composite paste so far, let alone about investigating the microstructure and mechanical properties of the full-Cu 3 Sn joints. At present, Cu 3 Sn IMCs are mainly prepared through heat treatment − and a thermal decomposition reaction. , For instance, a Cu 3 Sn IMC film was obtained by magnetron sputtering, electroplatingm or electroless-plating of Sn on Cu foil and then heating above 200 °C for even more than 24 h. Other researchers have used the thermal decomposition of expensive metal organic salts Sn­(acac) 2 and Cu­(acac) 2 to prepare the Cu 3 Sn IMC NPs. , Unfortunately, these preparation methods have their own limitations, such as a long process time, a high process temperature, and environmental pollution.…”

“…44,45 For instance, a Cu 3 Sn IMC film was obtained by magnetron sputtering, 41 electroplatingm 42 or electroless-plating 43 of Sn on Cu foil and then heating above 200 °C for even more than 24 h. Other researchers have used the thermal decomposition of expensive metal organic salts Sn(acac) 2 and Cu(acac) 2 to prepare the Cu 3 Sn IMC NPs. 44,45 Unfortunately, these preparation methods have their own limitations, such as a long process time, a high process temperature, and environmental pollution.…”