Nyiko Chauke

Title : Tuning photoelectrocatalytic activities of BiVO4 nanofibers via annealing temperature

Abstract:

In the realm of sustainable energy and environmental remediation, photoelectrocatalysis has emerged as a promising technology for harnessing solar energy to drive chemical reactions. Bismuth vanadate (BiVO4) has gained considerable attention as a photoanode material due to its excellent light-absorption properties and photocatalytic efficiency. To optimize its photoelectrocatalytic activities, we investigated the impact of annealing temperature on BiVO4 nanofibers. In this presentation, we delve into the synthesis and characterization of BiVO4 nanofibers annealed at temperatures ranging from 450°C to 600°C. The objective of this study is to explore the structural and morphological changes that occur in BiVO4 nanofibers at different annealing temperatures and assess their effects on photoelectrocatalytic performance. We utilized various characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis spectroscopy, to investigate the crystallinity, morphology, and optical properties of the annealed nanofibers. The findings reveal that the annealing temperature significantly influences the crystalline phase, grain size, and light-absorption properties of BiVO4 nanofibers. These structural changes are directly correlated with the photoelectrocatalytic activities of the material. As such, by systematically varying the annealing temperature, we gain insights into the optimal conditions for enhancing the nanofibers' performance in photocatalytic water splitting, pollutant degradation, and other solar-driven reactions. This study, therefore, highlights the importance of controlled annealing as a versatile tool for tailoring the properties of photoanode materials and advancing the field of photoelectrocatalysis. Understanding the relationship between annealing temperature and the photoelectrocatalytic activities of BiVO4 nanofibers is pivotal for developing efficient and sustainable energy conversion and environmental remediation technologies.

Audience Takeaway Notes: 

• Optimal Annealing Conditions: Understand the impact of annealing temperature on the structural and morphological properties of BiVO4 nanofibers, providing insights into the optimal conditions for enhancing photoelectrocatalytic performance.
• Characterization Techniques: Gain knowledge of various characterization techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis spectroscopy, and how these methods can be applied to investigate crystallinity, morphology, and optical properties of nanofibers.
• Correlation with Performance: Learn about the direct correlation between structural changes induced by annealing temperature and the photoelectrocatalytic activities of BiVO4 nanofibers, providing a deeper understanding of the relationship between material properties and performance.

Biography:

Dr Nyiko Chauke is a postdoctoral research fellow at the Catalysis Group of the Advanced Materials Division. He is currently working on the development of TiO2-based photocatalytic materials for utilisation in different wastewater treatment projects within the Mintek business units. Nyiko holds a Ph.D. and an M.Sc. in Chemistry from the University of Johannesburg and the University of Limpopo, respectively. He had worked in a postdoctoral role with the University of South Africa before moving to Mintek and also worked as a Part-time lecturer at the Tshwane University of Technology and the University of Limpopo. His view on wastewater treatment research is concentrated on the creation of novel and incredibly effective techniques for purifying water pollutants and aims to utilise his experience in contributing to the overall effective performance of the AMD in Mintek.