Over the past decade, technological prospects have driven tremendous progress in the synthesis of gold nanocrystals of various sizes and shapes1. For many applications, it is indeed of crucial importance to use nanoparticles with a predefined shape and size. Electron tomography is therefore often used to examine the 3D shape of nanoparticles2. However, since the acquisition of the experimental tilt series of 2D projection images are very time consuming, it is difficult to obtain statistical results concerning the 3D shape of nanoparticles. Furthermore, the long acquisition time also hampers the possibility to study in-situ processes in three dimensions.
Here, we make use of a novel electron acquisition method to circumvent these problems allowing us to acquire a full tilt series within a few minutes. As a validation, we compare the 3D reconstructions of single gold nanoparticles using the conventional tomography approach and our novel fast acquisition approach, which show a good agreement between both reconstructions.
This novel method enables us to not only get statistically relevant 3D information on the growth process of gold nanoparticles but also to track heat-induced morphological changes in metal nanoparticles. Specifically, I will present results on the growth process of anisotropic branched gold nanoparticles and the in-situ reshaping behaviour of gold nanostars as well as its effect on their optical properties. In addition, the approach presented here is generic and can hence be applied to a wide variety of nanoparticles made of different materials and in various shapes.