Achieving Controllable Liquid‐Solid Phase Transitions in Metallic Nanoparticles Through Electron Beam Irradiation
Chenjia Zhang, Pengfei Nan, Ningyan Cheng, Chaojun Zhang, Hongzheng Wang, Lunyong Zhang, Binghui Ge, Yixuan He, Hongxian Shen, Fuyang Cao, Jianfei SunABSTRACT
Nano‐additive manufacturing (NAM) endows the prospection to build complex 3D nano‐sized structures with high flexibility, however it requires manipulating the liquid‐solid phase transition at nano‐scale resolution, which remains a great challenge. In this study, we realized controllable liquid‐solid reversible phase transition of metallic nanoparticles by using electron beam irradiation. Alternating melting and crystallization were induced in Sn and In‐Sn nanoparticles at the room temperature by applying an appropriate electron dose rate. For Sn nanoparticles, the temporal fraction of crystalline states can be quantitatively tuned from 1.41% to 90.58% by varying the dose rate from 2.21 × 10 5 to 0.66 × 10 5 A/m 2 , while the crystallization cycles increase from 11 to 26 and then decrease to 3. Similar behaviors were realized in the In‐Sn system as well. This tunability enables precise control of the melting and crystallization behavior of an individual metallic nanoparticle by adjusting the electron dose rate. A quantitative thermal model is proposed that phase‐dependent particle‐substrate thermal conductance controls the balance between beam‐induced heating and substrate heat dissipation, leading to temperature oscillations across the phase‐transition threshold and enabling reversible melting‐crystallization behavior.