University of Pretoria student Bianca Gevers has won the Young Persons’ Lecture Competition in South Africa, while also placing second in the Young Persons’ World Lecture Competition. The Competition, which was hosted by the UK-based Institute of Materials, Minerals and Mining (IOM3), invites students and professionals up to the age of 28 to deliver a short lecture on a subject related to materials, minerals, mining, engineering and more. 

This year, the prize included a laptop, cash and membership to the IOM3 in South Africa and the UK. “I am excited and grateful for both these achievements,” says Gevers, who is pursuing a PhD in Chemical Engineering. “For most participating countries, the event usually comprises multiple stages, with regional competitions from which each winner competes in the country competition. So, there is a large number of participants that are filtered out before the final event. It was an honour to represent South Africa in the final.”

Her presentation was titled ‘Engineering Photoactive Materials for Renewable Energy Generation’. “The engineering of photoactive materials concerns changing the properties of materials used in renewable energy generation,” Gevers explains. “There are several properties that must be understood, tailored and perfected in a material for it to be functional for advanced applications. Engineering these properties means changing them, studying them and, hopefully, being able to predict (to some extent) sensical alterations to increase their activity.”

Her presentation, she explained, began with an introduction to renewable energy generation using sunlight and an explanation of the mechanistic requirements for its applications. A well-known application is the use of photovoltaic cells to absorb sunlight and generate electricity through processes occurring within the material. To do this, the material must absorb photons (light) and, in doing so, generate something called an exciton – essentially an excited electron that, through the absorption of a photon, leaves its position in the material to create an empty spot (a hole). These processes are also fundamental to photoelectrochemical and photocatalytic applications.

“This is the process we make use of to harvest the energy generated in photoactive materials,” Gevers says. “The harvestable energy can be electricity or even chemical compounds.”

The doctoral candidate says she chose to study chemical engineering instead of chemistry because of its practical application focus, but still loves the detailed understanding of the processes involved. “This is why, after completing my BEng, I opted to pursue postgraduate studies with a focus on the science and engineering of materials.”

She thanks Professor Johan Labuschagne, her research supervisor, for giving her exposure to conferences where she has presented prior to this event and the freedom to take part in contests such as the Young Person’s Lecture Competition. She also thanks the people that gave her feedback (David Viljoen and Professor Kathy Sole) and the opportunity for a dry-run (Wendy Knott-Craig) of her presentation before the international Competition. “I am immensely proud of her,” says Prof Labuschagne. “I have had the privilege of working with her at an undergraduate level, and I knew she would go far. Bianca has a very bright future ahead of her.”