Chemistry Weekly Seminar - Ruwaid Rafiuddin
PhD student Ruwaid Rafiuddin from the Grosvenor Group will present a seminar on his PhD research.
Title: A Structural and Spectroscopic Investigation of Rare-Earth Phosphates
Fossil fuels continue to remain the major source of energy production despite being the leading contributor to CO2 emissions. In order to combat climate change, alternate technologies are required to meet the global energy demands and nuclear technology is one such technology that provides energy with reduced carbon emissions. However, the waste generated by the nuclear industry is radioactive and robust host matrices are required for long term waste storage. In the early 1980s, crystalline materials were proposed to sequester nuclear wastes and since then materials with different crystal structures have been investigated for waste sequestration applications. Among the many materials studied, rare-earth phosphates (REPO4) adopting the monazite and xenotime structures were proposed as potential candidates for encapsulation of radioactive wastes due to their high resistance to radiation damage. The focus of my Ph.D. research was to understand the electronic structure and structural stability of rare-earth phosphates using synchrotron X-ray absorption spectroscopy. In the first part of this talk, I will discuss the effect of synthetic method and the size of the rare-earth ions on the structure of rare-earth phosphates followed by a discussion of their electronic structure using X-ray absorption near-edge spectroscopy (XANES). The structural response of rare-earth phosphates to radiation damage will be presented in the second part of this talk. Finally, I will present my ongoing work in which I am investigating the chemical durability of rare-earth phosphates.