Surface and materials science innovations are critical to high-performance energy systems. Project experiments conducted at NETL's Surface and Materials Science Laboratories characterize the structure, composition, and chemistry of systems and materials. There, scientists investigate theoretical and fundamental phenomena in support of fossil fuel program requirements and advanced technology development. Researchers use these laboratories to study catalysts, metals, and alloys, and to tackle and solve the nation's most pressing energy issues, including hydrogen separation, methane hydrates, and carbon sequestration. Studies are conducted in close cooperation with the NETL Computational Science team and with collaborative researchers.

A key asset for these studies is the Labs' state-of-the-art Omicron Surface Analysis and Imaging System. This ultrahigh-vacuum system integrates a broad suite of surface analysis and imaging tools into one single vacuum chamber. Techniques supported include:

• X-ray Photoelectron Spectroscopy
• Ion Scattering Spectroscopy
• Low Energy Electron Diffraction
• Auger Electron Spectroscopy
• Scanning Tunneling Microscopy
• Atomic Force Microscopy

Additional equipment and instrumental tools and resources include:

• Polarization Modulation Infrared Reflection Absorption Spectroscopy – A Fourier Transform PM-IRRAS system is used for studying the surface chemistry of metal foils. The system is coupled to a vacuum reaction cell capable of temperatures up to 1500 Kelvin.
• Raman Spectroscopy and Microscopy – Dispersive and Fourier Transform Raman spectrometers are used for studying the vibrational and electronic properties of various materials. Raman spectroscopy is well-suited for high-pressure experiments and several variable-temperature, high-pressure (up to 300 atmospheres) cells are available. The Raman systems have been used for in-situ studies of gas adsorption in nanoporous separation membranes. They have also been used extensively for studying the dissociation and formation properties of methane hydrates.
• Variable Temperature and Pressure Infrared System – A unique, cryogenic vacuum system is coupled to a Fourier Transform Infrared Spectrometer. The vacuum chamber is capable of sample temperatures from 5-700 Kelvin and pressures from 10 -9 to 760 Torr. This system has been used extensively for studies of gas adsorption in carbon nanotubes, metal-organic frameworks, and other novel porous materials.
• Physisorption and Chemisorption Instrumentation – High-pressure isotherm capabilities include a volumetric isotherm instrument with capabilities up to approximately 150 atmospheres, as well as a gravimetric system capable of pressures up to approximately 48 atmospheres. Low-pressure instrumentation is capable of collecting high-resolution isotherms up to 1 atmosphere. Chemisorption, surface area, and pore size studies are also possible with the low-pressure instrumentation.
• X-ray Diffractometer – X-ray diffraction is used for the study of solid materials. Applications include crystalline phase identification and quantification, crystallite size determination, and preferred orientation measurements. Instrument capabilities include flexible sample stages to accommodate a range of samples and a hot stage capable of heating samples in situ to 1200°C under vacuum or controlled atmosphere. The International Centre for Diffraction Data (ICDD) inorganic phase data base is available for routine phase identification.  
• Scanning Electron Microscopy – An SEM with Energy Dispersive Spectroscopy (EDS) is used for routine analysis. Samples can be quickly analyzed for morphology to a resolution of about 5 microns and elemental composition (carbon and heavier).  
• X-ray Photoelectron Spectrometer – A stand-alone XPS instrument is used for near-surface and routine surface analysis. This instrument is equipped with monochromatic Al and standard Al/Mg X-ray sources. Unique capabilities include the ability to determine near-surface composition as a function of depth through depth profiling or angle-resolved studies, plus the ability to map the distribution of species on the surface at a 30-µm resolution. Materials can be heated or cooled in-situ or be moved to an attached reaction chamber for treatment with a variety of gases at elevated temperatures.  
• Digital Microscope – A digital microscope is available to study samples at magnifications of 25 to 5000x. Feature dimensions can be quantified and 3-dimensional images can be generated using the microscope's software package.

X-Ray Photoelectron Spectrometer Instrumentation

For more information contact Christopher Matranga , Bret Howard , or John Baltrus.