利用脉冲激光沉积技术制备镍纳米颗粒及其生长过程中的应变场模拟

Formation and Strain Distribution of Ni Nanoparticles Fabricated by Pulsed Laser Deposition

利用脉冲激光沉积技术和快速退火成功地制备了镶嵌在非晶Al2O3薄膜中的Ni纳米颗粒,用高分辨率透射电子显微镜观察到镶嵌在非晶Al2O3薄膜中的Ni纳米颗粒,用有限元算法系统地模拟了Ni纳米颗粒生长过程中的应变场分布.研究发现:在Ni纳米颗粒的生长过程中,纳米颗粒受到母体Al2O3材料的非均匀的偏应变的作用,而且随着Ni纳米颗粒的长大,纳米颗粒受到母体Al2O3材料的非均匀偏应变也逐渐增加.这种非均匀偏应变对于纳米颗粒的晶格结构和形貌有较大的影响,可以通过调节Ni纳米颗粒生长过程中的应变场来实现对Ni纳米颗粒界面态的调控,从而进一步优化Ni纳米颗粒的物理性能.

Ni nanoparticles embedded in the amorphous Al2O3 matrix were fabricated by using pulsed laser deposition and rapid thermal annealing.The results from high-resolution transmission electron microscope also revealed that the complete isolation of Ni nanoparticles embedded in amorphous Al2O3 matrix.The growth strain of Ni nanoparticle embedded in the Al2O3 matrix was investigated.Finite element calculations clearly indicate that the Ni nanoparticle incurs a net deviatoric strain.With the growth of Ni nanoparticle,the larger Ni nanoparticles incur stronger net deviatoric strain,which will have much influence on the structure and morphology of Ni nanoparticles.Strain engineering is an effective tool for tailoring the properties of Ni nanoparticles.