Commensurate with the departments strengths in materials chemistry, a wide range of instrumentation is available for the analysis of the surface and bulk of solid samples. Surface characterisation can be carried out using scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and nitrogen physisorption. Powder X-ray diffraction (XRD) and X-ray fluorescence (XRF) instuments are also available for bulk analysis.
A Philips MPD3710 system is used for PowerXRD measurements. Phase identification can be made by comparison to known materials and currently PXRD files for 27,000 compounds are held in libraries (MacDiff and ICSD).Measurements of polymorph content in phase mixtures can be made as well as the percentage crystallinity of samples and particle sizes.Quantification is carried out by Rietveld analysis for determination of absolute content and structure determination.The instrument has been used in problems such as identifying inorganic contamination in pharmaceutical compounds, determining the polymorph structure of pharmaceuticals and the mineral phases of silicas, and particle sizing in superalloys.
To support the PXRD facilities, the department also has a differential scanning calorimetry (DSC) instrument from Setaram to study polymorph systems and heat evolution and absorption in chemical and structural reactions.The PXRD facilities are supported by laser particle size equipment. These instruments have proven useful in determining the polymorph phase content in pharmaceutical compounds, quantifying energy yields of waste sludges on incineration, and measuring the particle size distribution in alloy powders. Further information about these instruments can be obtained from Prof Michael Morris or Dr Justin Holmes.