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Andrew J Allen (Fed)

Physical Scientist, Materials Measurement Science Division

Research Interests

  • X-ray and neutron scattering-based microstructure characterization to address technological barriers in advanced materials development, for example:
  • Nanoparticle formation, assembly and interaction, for industrial, biomedical and environmental health applications (including RM development in collaboration with National Cancer Institute).
  • Structure-property relationships in films, coatings and energy materials, including high-k dielectric films, thermal barrier coatings and solid oxide fuel cell materials.
  • Fundamentals of cement hydration, including the effects of additives and environmental conditions on concrete used in the nation's infrastructure.
  • In operando characterization of selective gas sorption phenomena in advanced sorbents and carbonation processes relevant to addressing the nation's needs for climate change.
  • X-ray and neutron studies of mesoscale equilibrium and non-equilibrium dynamics relevant to advanced materials processes, e.g., ceramics additive manufacturing and densification, or precipitation kinetics in additive manufactured alloys.

Postdoctoral Research Opportunities
Microstructure of Energy Conversion, Storage, and Additive Manufacturing Materials
(Research Opportunity no. 50.64.31.B7417):

Control of microstructure, internal dynamics and chemistry is of primary importance in determining the performance and viability of solid oxide fuel cells, hydrogen fuel cells, carbon capture materials, and other systems that advance the hydrogen economy, promote US energy independence, or simply advance the Nation’s industry, e.g., through Additive Manufacturing.  The relevant scale range for void and phase microstructure (e.g. interfacial morphology, sintering or annealing), as well as for chemical site reactivity (e.g., combustion, reforming, corrosion) extends from the micrometer down to the sub-nanometer scale regime.  Our goal is to develop in operando measurement methods to quantify full three-dimensional void and phase microstructures and dynamics, including changes during service life and dependence on processing conditions.  These issues apply, e.g., to the electrodes and electrolyte of a SOFC; to the interfaces between them; and to any separate fuel-reforming hydrogen storage, or carbon dioxide capture material, where the microstructure must be related to the reaction site kinetics and to changes in site reactivity during service life.  This opportunity will address these interconnected issues by utilizing unique instrumentation, developed by NIST and its collaborators, and located at the Advanced Photon Source, the National Synchrotron Light Source II, and the NIST Center for Neutron Research.  Opportunities exist for investigating novel energy materials and devices including batteries, solid oxide fuel cells, energy harvesting devices, photovoltaics, and additive manufactured components.

For more information...

Carbon (CO2) Capture Materials
(Research Opportunity no. 50.64.31.B8183):
Many industrial processes generate CO2 as a by-product, which is released to the atmosphere and contributes to global warming.  Clean, low-CO2 emission technology, which requires carbon capture (CO2 removal from flue gas by solid-state sorbents), is critical to meet our Nation’s energy and manufacturing needs in an environmentally sustainable manner.  Similarly, CO2 adsorption in shale minerals during enhanced oil and gas recovery will also play a critical role.  Low CO2 emission technology depends on transient gas/solid material interactions.  Such interactions cannot be inferred from initial or final state materials property measurements such as sorbent microstructure, but must be measured in situ during the sorption or release process.  This project focuses on the design, construction, and application of a suite of in situ measurement platforms for use with NIST’s state-of-the-art neutron and synchrotron X-ray scattering facilities, capable of interrogating critical carbon capture properties across the range of candidate CO2 sorbent solid materials, as well as oil and gas shales.  Measurements using the platform suite will focus on in situ determination of changes in structure, microstructure, atomic bonding, and dynamics in sorbent materials during the sorption and release of CO2 under controlled conditions of temperature, pressure, humidity, and atmosphere.  X-ray or neutron diffraction analysis and thermogravimetric analysis will be carried out in situ with samples that are simultaneously undergoing evolved gas analysis.


    •    Plenary Speaker, 18th International Conference on Small-Angle Scattering, Campinas, Brazil, 2022
    •    Editor-in-Chief of International Union of Crystallography (IUCr) Journals, 2018 - present
    •    Department of Commerce Silver Medal, Group Award, 2016
    •    Main Editor, Journal of Applied Crystallography, 2014-2018
    •    Plenary Speaker, 15th International Conference on Small-Angle Scattering, Sydney, Australia, 2012
    •    Department of Commerce Bronze Medal Award, 2009
    •    Department of Commerce Silver Medal, Group Award, 2008
    •    Best Paper Award, Journal of Thermal Spray Technology, Volume 14, 2005
    •    Co-Editor, Journal of Applied Crystallography, 2002-2014
    •    NIST Bronze Medal, Group Award, 1998
    •    Best Paper Award, International Thermal Spray Conference, France, 1998
    •    Advisory Editor, Journal of Physics: Condensed Matter, 1991-96
    •    Open Exhibition Scholarship, Oxford University, 1974-1977


Reproducible Sorbent Materials Foundry for Carbon Capture at Scale

Austin McDannald, Howie Joress, Brian DeCost, Avery Baumann, A. Gilad Kusne, Kamal Choudhary, Taner N. Yildirim, Daniel Siderius, Winnie Wong-Ng, Andrew J. Allen, Christopher Stafford, Diana Ortiz-Montalvo
We envision an autonomous sorbent materials foundry (SMF) for rapidly evaluating materials for direct air capture of carbon dioxide ( CO2), specifically
Created October 9, 2019, Updated May 3, 2023