Au/Cu Bimetallic Nanoparticles via Double-Target Sputtering onto a Liquid Polymer

Area of Science:

• Materials Science
• Nanotechnology
• Physical Chemistry

Background:

• Bimetal alloy nanoparticles (NPs) are crucial in various applications.
• Producing homogeneous alloy NPs with controlled composition remains challenging.
• Gold-copper (Au/Cu) alloys exhibit unique properties but require precise synthesis.

Purpose of the Study:

• To develop a facile method for synthesizing Au/Cu alloy nanoparticles.
• To investigate the influence of sputtering parameters on NP composition and properties.
• To demonstrate the versatility of the synthesis technique on different substrates.

Main Methods:

• Utilized a double-target sputtering technique with independent control over gold (Au) and copper (Cu) targets.
• Deposited NPs onto a liquid polymer substrate, polyethylene glycol (PEG).
• Characterized NP formation, composition, and structure using scanning transmission electron microscopy-energy-dispersive X-ray elemental mapping.

Main Results:

• Successfully produced Au/Cu alloy NPs with a solid solution structure.
• Demonstrated that altering sputter currents precisely tailored NP composition without significantly affecting particle size.
• Observed similar NP characteristics when sputtered onto PEG and carbon-coated grids, and via alloy target sputtering.

Conclusions:

• The double-target sputtering method offers independent control over alloy composition for Au/Cu NPs.
• This technique is advantageous for creating tailored alloy nanoparticles for diverse applications.
• The process is adaptable to various substrates, including biocompatible polymers like PEG.