Agglomeration and Sintering in Annealed FePt Nanoparticle Assemblies Studied by Small Angle Neutron Scattering and X-Ray Diffraction

In this work we give a detailed account of the use of small angle neutron scattering to study the properties of polymer mediated, self assembled nanoparticle arrays as a function of annealing temperature. The results from neutron scattering are compared with those obtained from x-ray diffraction. Both techniques show that particle size increases with annealing temperatures of 580 C and above. They also show that the distribution of particle diameters is significant and increases with annealing temperature. The complementary nature of the two measurements allows a comprehensive structural model of the assemblies to be developed in terms of particle sintering and agglomeration. To realize the potential of nanoparticle assemblies as a monodispersed data storage medium the problem of particle separation necessary to avoid sintering and agglomeration during annealing must be addressed.

在这项工作中，我们详细阐述了利用小角中子散射来研究聚合物介导的自组装纳米粒子阵列的性质随退火温度的变化情况。将中子散射的结果与X射线衍射所得结果进行了比较。两种技术都表明，在580℃及以上的退火温度下，粒子尺寸会增大。它们还表明，粒径分布显著，且随退火温度升高而增大。这两种测量方法的互补性使得能够根据粒子烧结和团聚情况建立起组装体的综合结构模型。为了实现纳米粒子组装体作为单分散数据存储介质的潜力，必须解决在退火过程中为避免烧结和团聚所必需的粒子分离问题。