Research Fellows Directory
Dr Olga Degtyareva
University of Edinburgh
Hydrogen is known to form compounds with many elements in the periodic table. Among those, the metal hydrides are of particular interest due to their application in hydrogen storage for fuel cells or heat storage for the solar-energy industry. Also, in fundamental science, metal hydrides become increasingly important due to their relevance to the study of the behaviour of pure hydrogen at extreme conditions and as materials with potentially interesting properties. Because of the very low solubility of hydrogen at ambient conditions in platinum, as well as most other transition metals, these elements do not form hydrides.
High pressure can provide a different route to the synthesis of new compounds, initiating chemical processes that would not happen otherwise. By bringing atoms closer together, high pressure forces short bonds to participate in novel chemical reactions. This can result in the formation of new materials with advanced properties such as extreme hardness (e.g. the formation of diamond from graphite). However, high temperatures are usually required in addition to high pressures to initiate the synthesis or a phase transition. A number of transition metals that do not react with hydrogen at normal conditions have been shown to form hydrides at high temperatures and moderate pressures.
We have investigated the formation of hydrides of platinum and rhenium under high pressure. Both these metals are widely used in the high-pressure research but there is no systematic information or understanding of the hydride formation in these metals and of their properties.We have discovered formation of new materials with interesting properties that have not been predicted earlier.