Versatile x-ray spectroscopy facility

X-ray spectroscopies are fundamental tools for characterising the nature of chemical bonding and chemical composition in materials. We have established an X-ray spectroscopy facility centred around environmental near-ambient pressure X-ray photoelectron spectroscopy (NAP XPS) to overcome some of the limitations of conventional ultra-high vacuum XPS (UHV XPS).

Volatile or liquid samples must typically be cooled or frozen prior to measurement under UHV which can change sample behaviour. In contrast, environmental XPS enables studies of materials containing volatile components (e.g. solvents, adsorbed gases, biological and biomaterials, pastes and suspensions) which can be beneficial for understanding the relationship between chemical composition and conditions of manufacture or end application. 

The instruments also enable studies of electrically insulating samples, whole devices and dynamic processes, and depth profiling.

Equipment

• SPECS EnviroESCA system with Ar cluster source (GCIB), charge neutralisation, sample heating and cooling, control of gas phase composition and XPS up to 30 mbar
• UHV XPS module with Al (monochromatic) Zr and Cr Kα sources and noble gas ion etching
• High pressure sample preparation chamber for sample transfer to UHV
• Sample transport devices (‘suitcases’), linking to UHV, glovebox and cleanroom environments
• In-situ and operando cells for synchrotron XAS, including environmental chambers for electron-yield and optical luminescence yield NEXAFS
• Crystallisers and liquid jet devices for probing of liquids with synchrotron X-ray absorption, X-ray Raman scattering, X-ray scattering and X-ray Pair Distribution Function measurements.

The facility is linked to the Diamond Leeds collaboration with a view to supporting users in design, application and preparation of experimental programmes with advanced X-ray characterisation at the UK’s synchrotron facility, Diamond.

The facility is also co-located with other facilities in the Sir William Henry Bragg Building such as the Multifunctional Heterostructured Materials Facility, our cleanroom facility and other complementary facilities and labs for sample preparation and characterisation. 

Applications

• Characterisation of samples and devices containing volatile components (e.g. solvents, absorbed gases, biological and biomaterials, pastes and suspensions), without cryogenic cooling
• Investigations of electrically insulating samples
• Studies of whole devices and dynamic processes
• Depth profiling of molecular materials 
• High throughput environmental XPS

Partners and sponsors

The Henry Royce Institute,  is the UK's National Centre for Research and Innovation of Advanced Materials. It operates as a hub and spoke model, with the hub at The University of Manchester, and spokes at the founding partners, initially comprising the universities of Sheffield, Leeds, Liverpool, Cambridge, Oxford and Imperial College London, as well as UKAEA and NNL. 

Diamond Light Source is the UK’s national synchrotron. Diamond is one of the most advanced scientific facilities in the world, and its pioneering capabilities are helping to keep the UK at the forefront of scientific research 

Members of staff

Professor Sven Schroeder, Royal Academy of Engineering Bragg Centenary Chair in Engineering Applications of Synchrotron Radiation

Research interests: In situ process monitoring in microreactors, state-of-the-art spectroscopies and microscopies, interface and colloid science, surface and solid state physics, instrument development and synchrotron radiation experiments (in situ X-ray spectroscopy, scattering and fluorescence). 

Dr Beth Willneff, Facility Manager and Senior Research Fellow

Research interests: Theory and practice of XPS and XAS for in situ or operando materials characterisation in the context of multiscale science and engineering, small-molecule; crystallisation,; heritage science, catalysis, tribology and other areas. Particularly interested in linking fundamental and industrial research.

Dr Andrew Britton, Research Officer 

Research interests: XPS, NAP-XPS, HAXPES, surface science, interfaces, NEXAFS (or XANES), molecules on surfaces, charge transfer dynamics, magnetic molecules and ferrolectric materials. 

Contact

Academic PI: Professor Sven Schroeder

Facility Manager: Dr Beth Willneff

Research Officer Dr Andrew Britton

Internal enquiries:  https://leeds365.sharepoint.com/sites/Bragg-XPS-XRD