Durham University's Core Equipment Award 2022

Powder X-ray Diffraction (PXRD) is the most powerful technique for understanding the structure, properties and function of solid-state materials. A beam of X-rays is directed into the sample and the emerging pattern can be detected and analysed both spatially and by energy and used to determine many properties of the sample. Crucially a macroscopic crystal is not required which is needed in many other X-ray based techniques.

In chemistry it is the primary method for analysing newly-synthesised or controlled-morphology compounds with novel physical properties (e.g. functional materials for energy- and environment-related application, such as battery materials, fuel cell materials, lighting phosphors and oxygen storage materials); it's required to understand the structures of heterogeneous catalysts (zeolites, oxides, nanoparticles) needed for environmentally sustainable chemical processes and emissions control; and it is crucial for understanding and controlling the solid form of pharmaceuticals. In condensed matter physics, PXRD helps unravel the crucial atomic rearrangements that might accompany important property changes such as superconductivity, magnetism and skyrmion formation.

In materials science and engineering it's needed to characterise samples such as graphene and its derivatives and solar cell materials. In earth sciences it is the principal tool for phase identification and quantification of minerals and clay content and how they evolve under different environmental conditions and is an important consideration in areas such as the built environment.

Outside the direct EPSRC remit, though linked through multidisciplinary research that is supported by both EPSRC and BBSRC, in biosciences, even protein structures have been solved by powder diffraction. The technique is of increasing importance in cultural heritage, as exemplified by recent Durham research highlights on ancient manuscript pigments and the provenance and production processes of archaeological ceramics where instrumentation has been developed with EPSRC funding for specific applications.