Jebin Jestine Email & Phone Number

Ashford, Gb

Swansea

Project on developing characterisation workflows for functional coatings in collaboration with Zeiss. Within my research I have experience of using the Zeiss Xradia 520 (lab-based X-ray microscopy/microCT system) on a variety of samples from the carbon-based perovskite solar cell (CPSC) to biological samples such as dermal denticles from Thornback ray. The focus with CPSC was to create a characterisation workflow for 3D characterisation of the sample. The challenges came from the resolution requirement due to the very thin layers. A two-part multimodal workflow was created where a small (~100-micron diameter) cylindrical sample was FIB milled (Zeiss Crossbeam 550) prior to 3D X-ray microscopy characterisation on a lab-based system (Zeiss Xradia Versa 520) capable of spatial resolution of 700 nm. This was used as an initial characterisation step to validate that low density carbon flakes can be resolved against carbon black powder and porosity. The second part of the workflow involved creating another separate cylindrical sample (~100-micron diameter) using laser femtosecond milling (Zeiss Crossbeam laser 550) prior to phase and absorption-contrast X-ray microscopy on a different lab-based system (Zeiss Xradia 810 Ultra 5.4 keV). This was the first time this type of device was characterised in 3D. I carried out optical microscopy along with scanning electron microscopy (SEM) to direct the next steps of characterisation with both the CPSC and dermal denticle sample. X-ray imaging revealed distinct greyscale differences, indicating a contrast in adjacent materials with possible chemical variation, and potentially mechanical differences. Targeted imaging was applied to study these layers and their interface further and understand if there is a difference in mechanical and chemical properties across the two regions. SEM and energy dispersive spectroscopy (EDS) were applied to a sample targeting the interface region, including the outer and inner layers (Zeiss Evo LS25).

Engineering Doctorate Engd, Materials Science

Characterisation of functinoal coatings using correlative microscpoy in collaboration with Carl Zeiss microscopy in the UK, Germany.

Education record