A cryo electron microscopy facility for materials research

Session

Poster Session Two

Authors

Dr Catriona McGilvery (1), Dr Michelle Conroy (1), Dr James Douglas (1), Prof Baptiste Gault (1, 2), Prof Finn Giuliani (1)

Affiliations

1. Imperial College London
2. MPIE

Keywords

cryo electron microscopy

technique development

battery materials

Atom Probe

plasma FIB

probe corrected TEM

Abstract text

In the materials sciences, cryo techniques have traditionally been implemented in biomaterials research for the preparation of samples, and subsequent imaging at cryo temperatures in the SEM and TEM.  However, over recent years a shift has occurred and cryo techniques have become increasingly important in addressing more traditional materials science problems.  For example, cooling samples during FIB preparation reduces structural distortion or other beam damage effects.    These samples may then be transferred to an electron microscope at room temperature for further analysis.  Alternatively, samples may be cooled in-situ in the TEM to reduce chemical or structural changes occurring due to the electron beam.  Alongside these, there have been great advances in cryo sample preparation by FIB for hydrated or biological samples which can then be transferred under cryo conditions directly into an electron microscope and then analysed at liquid nitrogen temperatures.  

 

In 2021 Imperial College department of Materials was the recipient of a £10.3M EPSRC strategic equipment grant to build on the expertise already available in these areas and to apply them to Materials science questions.  A full cryo workflow is being developed between a plasma FIB, probe corrected TEM and an Atom Probe, aided by a glove box, such that samples can go from preparation to final analysis fully under cryogenic and vacuum conditions. The instruments are equipped with cryo stages and holders allowing sample preparation, transfer and analysis to be carried out on the same region of sample without the sample ever being brought back to room temperature.  This will allow a wide range of materials systems to be studied with a particular focus on battery materials, liquid solid interfaces, and materials containing light elements with high mobility.  Here we will present details of the new cryo facility and results from our preliminary investigations.