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Thrust 2: Hierarchical Framework Materials

Research in this thrust will investigate bulk solids or membranes with interconnected negative space on multiple length scales and containing active sites—atomic, molecular, or nanoparticulate—with control over the size and spatial distribution of both pores and active sites. Developments in this area will be useful in hydrocarbon transformation, biomass conversion, exhaust treatment, and building energy efficiency.


Anomalous water expulsion from carbon rods at high humidity.
Anomalous water expulsion from carbon
rods at high humidity.

Carbon Rods with Unexpected Humidity-driven Water Expulsion

DJ Heldebrant, D Lao, SK Nune, X-Y Yu

Water separations are critical for energy-related fields, notably CO2 capture, catalysis, bio-oil separations and energy storage. We are working to understand the carbon rod growth mechanisms and how to perfect the surface chemistries required to make up FeXSY(C) rod bundles that adsorb water at low humidity, and spontaneously expel half of the adsorbed water at high relative humidity. This is the first inorganic material known today that breaks from conventional water sorption behavior. This behavior offers potential for a transformative shift in water purification as water can now repeatedly adsorbed from a low humidity vapor stream and then expelled into a pure water stream.

Scalable Synthesis of Spinel Stabilized Metal Catalysts

Y Wang, J Liu, D Mei

The proposed research will provide fundamental understanding of the mechanisms involved in the scalable synthesis of high-purity spinel with controlled facets. The lattice of such high-purity spinel supports will be precisely tuned to stabilize the metal nanoparticles. The fundamental knowledge learned will guide rational design of stable supported metal catalysts for applications under harsh reaction conditions as encountered for biomass conversion and emission abatement.

Scanning electron microscope image of MFI zeolite synthesized in a spinning nuclear magnetic resonance rotor during an in-situ experiment.
Scanning electron microscope image of
MFI zeolite synthesized in a
spinning nuclear magnetic resonance
rotor during an in-situ experiment.

Robust Hierarchical Zeolite Frameworks

MA Derewinski, I Arslan, JZ Hu, JA Lercher

We are working to provide a molecular description on the formation and arrangement processes during synthesis of microporous crystalline silicates using PNNL's advanced measurement capabilities. We will use that knowledge as basis for the synthesis of nano-sized and mesoscopically structured zeolites with tailored chemical and textural properties. We are also working on stabilizing zeolites used in conversion of bio-derived compounds in liquid water environment via post-synthetic selective removal of structural defects.

Graphene Oxide Based Structured Laminar Membranes

DW Gotthold, I Arslan, R Devanathan, LS Fifield, D Li, W Liu, Y Shin

Laminar membranes, consisting of hierarchically stacked, overlapping molecular layers are a fascinating and promising new class of materials. To enable practical applications for this new class of structured materials, two fundamental questions must be answered. First, what is the mechanism responsible for water transport in laminar membranes (such as graphene oxide, or GOx), and what are the influences of structure and surface chemistry on the transport properties? Second, how does the laminar structure assemble, and how do we develop a scalable synthesis route to make commercially viable separation membranes? By developing a fundamental understanding of how these new laminar membranes assemble and function, we will enable the development of practical water separation membranes for a wide range of energy technologies.

MS3 Initiative