Achieving Controllable Liquid-Solid Phase Transitions in Metallic Nanoparticles Through Electron Beam Irradiation

Area of Science:

• Materials Science
• Nanotechnology
• Physics

Background:

• Nano-additive manufacturing (NAM) offers potential for complex 3D nanostructures but faces challenges in controlling nanoscale liquid-solid phase transitions.
• Precise manipulation of phase transitions at the nanoscale is crucial for advancing NAM capabilities.

Purpose of the Study:

• To achieve controllable liquid-solid reversible phase transitions in metallic nanoparticles using electron beam irradiation.
• To investigate the tunability of melting and crystallization behavior by adjusting electron dose rates.

Main Methods:

• Utilized electron beam irradiation to induce alternating melting and crystallization in tin (Sn) and indium-tin (In-Sn) nanoparticles at room temperature.
• Varied electron dose rates to quantitatively tune the temporal fraction of crystalline states and crystallization cycles.
• Developed a quantitative thermal model to explain the observed phase transition phenomena.

Main Results:

• Demonstrated controllable reversible melting and crystallization of individual metallic nanoparticles.
• Quantitatively tuned the crystalline state fraction in Sn nanoparticles from 1.41% to 90.58% by varying electron dose rate.
• Observed similar tunable behaviors in In-Sn nanoparticles, with adjustable crystallization cycles.

Conclusions:

• Electron beam irradiation provides a precise method for controlling nanoscale liquid-solid phase transitions in metallic nanoparticles.
• The tunability of phase transitions enables precise control over nanoparticle behavior for advanced manufacturing applications.
• A proposed thermal model highlights the role of thermal conductance in achieving reversible melting-crystallization.