3D Volume Microscopy and TEM Sample Preparation of Complex Hybrid Nanostructures

Use of a focused ion beam (FIB) in a dual beam, analytical scanning electron microscope (SEM) for serial ion beam sectioning of solids allows the investigation of the three dimensional (3D) chemical micro- and nanostructure over volumes of hundreds of cubic microns, so called 3D volume microscopy, at resolutions greater than that achievable using X-ray microtomography. In addition, it is possible to extract site-specific thin transmission electron microscopy (TEM) cross-sections for the higher resolution analysis of surfaces or interfaces within the microstructure. The use of a liquid nitrogen-cooled sample cryo-stage reduces ion beam damage and permits the application to beam-sensitive samples such as hybrid inorganic-organic materials, organics and also frozen samples which is otherwise extremely challenging. Furthermore, the inclusion of a cooled nanomanipulator and a scanning TEM (STEM) detector enables in-situ imaging of frozen TEM lamella that, in principle, could be cryo-transferred to an external cryo-TEM for additional analysis. As well as reducing damage in conventional inorganic materials, such a capability opens up new horizons for the characterisation of complex soft solids (and potentially liquid dispersions) used in a wide range of medical, chemical, structural and electronic applications.

In terms of economic impact, the University of Leeds has a longstanding track record of translating research to industrial end-users though direct collaboration, licensing of IP, or spin-out, forming a proven model for future translational activity. Many highly successful translational areas are of direct relevance to the potential output of the new cryo-FIBSEM capability, these include sectors such as medical technologies, complex particulate formulated products and ICT. Application in many of these areas will have significant wider societal benefits.
In terms of skills, the new equipment will enhance the skills of a range of postdoctoral researchers and also Ph.D. students in the 8 EPSRC Centres for Doctoral Training (CDTs) associated with Leeds and also those external users from outside Leeds. Additionally there will be impact on the skills of industrial collaborators and also Leeds undergraduates as part of research-led teaching.
We will ensure we communicate the importance and impact of science and engineering enabled by the new equipment to the wider public, policy makers, other funders, charities, governments and political leaders, and demonstrate societal and economic benefits.