A passion for scientific discovery and a commitment to solving real-world energy challenges have earned Tshedza Rasilingwani a Master of Science in Physics degree cum laude from Sefako Makgatho Health Sciences University (SMU), where her groundbreaking research explored ways to improve the performance and longevity of next-generation solar cells.
Rasilingwani’s MSc dissertation, titled Thermal stability/degradation of dye-sensitised solar cells with perovskite material, investigated one of the key challenges facing renewable energy technologies: the thermal instability and degradation of solar cells over time. Her research contributes to the growing body of knowledge aimed at improving the efficiency, durability, and commercial viability of solar energy systems.
Conducted through the Department of Physics at SMU, the study focused on dye-sensitised solar cells (DSSCs), a promising alternative to conventional solar technologies due to their relatively low production costs and high power-conversion potential. Despite these advantages, DSSCs continue to face limitations related to thermal degradation, which can significantly reduce their lifespan and performance.
“Renewable energy technologies are essential for addressing global energy demands and environmental challenges,” said Rasilingwani. “My research sought to understand how thermal conditions affect the stability of dye-sensitised solar cells and to identify ways of improving their performance through material optimisation.”
As part of the study, titanium dioxide (TiO₂) was synthesised using the sol-gel method and subjected to different annealing temperatures ranging from 450°C to 1200°C. Advanced analytical techniques, including X-ray diffraction, scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, and photoluminescence analysis, were used to evaluate the structural and optical properties of the material.
The findings revealed that increasing the annealing temperature improved the crystallinity and structural properties of titanium dioxide, making it more suitable for photovoltaic applications. Rasilingwani also fabricated perovskite-sensitised solar cells using titanium dioxide annealed at 600°C and evaluated their performance under simulated solar illumination.
“The results demonstrated that annealing temperature plays a significant role in enhancing the properties of titanium dioxide used in solar cell fabrication,” she explained. “This knowledge could contribute to the development of more stable and efficient photovoltaic devices in the future.”
Beyond her academic achievements, Rasilingwani gained extensive research experience during her postgraduate studies. Through her MSc research, she developed strong competencies in cleaning, transforming, and analysing experimental datasets, identifying patterns and trends, and producing clear visual reports to support scientific interpretation. She also served as a part-time laboratory demonstrator, mentoring undergraduate students, facilitating practical experiments, and contributing to the development of future scientists.
Her academic journey reflects a consistent record of excellence, having completed a BSc in Physics, followed by a BSc Honours degree in Physics, before progressing to her MSc studies. Throughout her training, she developed strong analytical, problem-solving, communication, and research skills that position her well for a future career in scientific research and innovation.
Rasilingwani said achieving her MSc cum laude serves as motivation to continue contributing to research that addresses pressing societal challenges. “I am passionate about advancing scientific knowledge and developing solutions that can make a meaningful impact,” she said. “This achievement encourages me to pursue further opportunities in research and innovation.”
Her success highlights the growing contribution of SMU graduates to scientific advancement and underscores the university’s commitment to excellence in teaching, learning, and innovative research. Through graduates such as Rasilingwani, SMU continues to strengthen its reputation as a leading health sciences university that produces skilled researchers capable of addressing national and global challenges through science and innovation.
By Tumelo Moila
