Research infrastructure
XPS Platform provides surface analysis by X-Ray Photoelectron Spectroscopy (XPS) technique. Full range of conventional XPS measurements is available including monochromatic Al Kα excitation, angle-resolved XPS, XPS imaging, and cryogenic measurements of hydrated (wet) samples. XPS, also known as Electron Spectroscopy for Chemical Analysis (ESCA), is now one of the most widely used tools in countless fields of science and engineering where advanced analysis of surfaces and interfaces is needed.
Andrey Shchukarev and AXIS Ultra DLD electron spectrometer
ImageMattias Pettersson
The X-ray photoelectron spectroscopy (XPS) platform is an open infrastructure at UmU enabling users both within UmU and outside to obtain analyses of the chemical composition of their sample surface. Knowledge of the elemental composition, oxidation state and spatial distribution of atoms at surfaces, near-surfaces, and interfaces is crucial to our understanding of key reactions in nature and technology. Surfaces are, after all, the immediate interface through which materials - as small as metal nanoparticles and bacteria, to as big as nuclear fuel reactors and spaceships - interact with their environments. All experiments are performed with AXIS Ultra DLD electron spectrometer manufactured by KRATOS Analytical Ltd. (UK). The new AXIS SUPRA+ spectrometer is under installation now and is expected to be in operation in November 2023.
The main fields of application at our XPS Platform facility are currently:
• Environmental samples, in particular the composition of mineral-aqueous solution interface • Biological specimens such as intact bacterial cells • Control of surface modification of materials for catalysis, bioseparation processes and antibacterial applications • Cellulose fibers and films • Commercial analysis for the external customers (industry, consulting agencies, etc.)
UmU XPS Platform represents the only facility in Sweden, and was the first in the world, who could routinely provide cryogenic XPS analyses. Furthermore, the XPS platform is the only facility for XPS analyses in Northern Sweden (north of Uppsala). The platform supports a unique field of research, developed at the Department of Chemistry involving investigations of fast-frozen samples including mineral-aqueous solution interfaces, interfaces of biomaterials with biologically relevant media, and surface chemistry of microorganisms. The platform also supports a large range of research projects by providing state-of-the-art surface analysis in areas including ecology, chemistry, physics, archaeology, molecular biology, dentistry and engineering.