Ofentse Makgae

affiliated with the university, D.Phil.

Research

Ofentse is a postdoctoral research fellow in environmental transmission electron microscopy (ETEM) within the national centre for high-resolution electron microscopy (nCHREM) at the Centre for Analysis and Synthesis (CAS). His research includes the direct observation of how hard surface coatings ((Al, Ti, Si)N) on power tools for metal machining are affected by high temperature, the presence of oxygen, and contact with the workpiece during the machining process using ETEM, where the changes in structure and chemical composition can be imaged at the atomic level in real-time. This enables studies of transitory processes that could not be seen if the materials were studied only after the processes had taken place (so-called post-mortem examinations). These factors can lead to chemical reactions and diffusion between the phases involved, and ultimately the deterioration of the surface coating. 

Ofentse completed his D.Phil. in Materials at the University of Oxford in 2020, under the supervision of Prof. Angus Kirkland and Dr. Emanuela Liberti. During his D.Phil., he worked on the in-situ and ex-situ characterisation of supported cobalt oxide nanocrystals, including the gas-solid redox reactions of cobalt oxide, using aberration-corrected TEM and exit wave restoration, as well as a combination of aberration-corrected scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS). Ofentse is a member of the Royal Microscopical Society, the European Society of Microscopy, Microscopy Society of Southern Africa, and the South African Chemical Institute.