Abstract
Nanoparticles have a wide range of applications due to their unique geometry and arrangement of atoms. For a precise structure-property correlation, information regarding atomically resolved 3D structures of nanoparticles is utmost beneficial. Though modern aberration-corrected transmission electron microscopes can resolve atoms with the sub-angstrom resolution, an atomic-scale 3D reconstruction of a nanoparticle using Scanning Transmission Electron Microscopy (STEM) based tomographic method faces hurdles due to high electron irradiation damage and “missing-wedge”. Instead, inline 3D holography based tomographic reconstructions from single projection registered at low electron doses is more suitable for defining atomic positions at nanostructures. Nanoparticles are generally supported on amorphous carbon film for Transmission Electron Microscopy (TEM) experiments. However, neglecting the influence of carbon film on the tomographic reconstruction of the nanoparticle may lead to ambiguity. To address this issue, the effect of amorphous carbon support was quantitatively studied using simulations and experiments and it was revealed that increasing thickness and/or density of carbon support increases distortion in tomograms.
Highlights
Nanoparticles have immense potential applications in various fields ranging from electronics [1] to renewable energy[2], medicine[3] to agriculture sectors[4] due to their unique physical [5] and chemical properties [6]
Simulation results: Figure 1 portrays the influence of supporting amorphous carbon film on the atomically resolved tomographic reconstruction of simulated disc shape single-crystalline non-defective silver nanoparticle from single projection using in-line 3D holography[9]
Column 1 and column 2 of Fig. 1 represent the simulated nanostructures comprises nanoparticle supported on amorphous carbon film and the reconstructed phases of the complex valued exit waves of various tp/tac ratios and density along [001] direction respectively
Summary
Nanoparticles have immense potential applications in various fields ranging from electronics [1] to renewable energy[2], medicine[3] to agriculture sectors[4] due to their unique physical [5] and chemical properties [6]. To study structure-property correlation precisely, atomically resolved 3D structural information of nanoparticle is very crucial[7] Tomographic techniques such as atom probe tomography (APT)[8] and electron tomography[9] are the most popular techniques for 3D reconstruction of nanostructures. Atomic resolution tomograms of NiO[28], CeO2 and MoS2 nanoparticles[29] have been presented in conference proceedings but the influence of supporting amorphous carbon films on atomically resolved tomographic reconstruction has not been considered yet which leaves ambiguity in final reconstructed tomogram. The motivation of this present work is to uncover the influence of supporting amorphous carbon films on tomographic reconstructions of nanoparticles quantitatively
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have