Research
Overview
We develop compositionally complex thin films and nanomaterials using advanced manufacturing — solution processing, electrochemical synthesis, and atmospheric-pressure plasma methods — paired with high-throughput exploration. By engineering atomic-scale structure and chemical disorder, and probing materials with electron microscopy, x-ray scattering, and spectroscopy, we uncover the structure–property relationships that enable new performance regimes. Our application focus includes sustainable energy, clean chemical production, and materials for extreme environments, ensuring our discoveries are both fundamental and impactful.
Spray Plasma Processing of Nitrogen Doped Carbon Materials
Spray-plasma processing (SPP) enables the rapid, scalable formation of nitrogen-doped carbon materials by coupling precursor delivery with nonequilibrium plasma chemistry. In this approach, nitrogen-containing molecular or polymeric precursors are atomized into micron-scale droplets and introduced into an atmospheric-pressure plasma jet, where ion bombardment, radical chemistry, fragmentation, crosslinking, and carbonization occur concurrently. These synergistic pathways promote nitrogen incorporation, defect generation, and controlled carbon hybridization without the high temperatures or long processing times common to thermal synthesis routes.
By tuning precursor chemistry, plasma conditions, and injection geometry, we access graphitic, pyridinic, and pyrrolic nitrogen configurations, engineer disordered and partially graphitized domains, and modulate porosity and surface functionality. This enables the creation of N-doped carbon films and architectures with emergent electronic and catalytic properties.
We deploy these plasma-processed carbons across heterogeneous and electrochemical catalytic contexts, where tunable bonding motifs and defect chemistry play key roles in oxygen reduction, hydrogen-evolution and oxidation reactions, CO₂ and nitrogen conversion, and selective organic transformations. The ambient-pressure nature of SPP makes it a scalable and sustainable platform for producing next-generation catalytic materials.
Students: Tanikka Swope
Spray Plasma Processing of High Entropy Oxides
Spray Plasma Processing (SPP) combines the versatility of traditional solution processing techniques—such as spin-coating, spray-coating, dip-coating, and blade-coating—with the scalability and molecular-level control offered by atmospheric pressure plasma processing. In SPP, an ink of virtually any composition—ranging from metal salts to colloidal suspensions—is injected directly into an atmospheric pressure plasma discharge. By precisely controlling the ink and plasma chemistries, we can design and synthesize metals, oxides, polymers, and nanocomposite thin films with tailored properties.
Our current research focuses on using SPP to develop high entropy oxides (HEOs), an emerging class of materials that incorporate five or more cations into a single oxide lattice. These materials exhibit a remarkable range of properties, making them highly promising for applications such as oxygen reduction catalysts and advanced hydrogen barrier coatings. The high throughput and scalability of SPP uniquely position us to explore the vast compositional space of HEOs, overcoming one of the greatest challenges in leveraging their potential for real-world applications.
Students: David Porras, AJ Leone
Atmospheric Pressure Plasma Modification of Natural Materials
Atmospheric-pressure plasma processing enables precise, solvent-free surface modification of natural materials such as wood and mycelium, allowing us to tune their chemistry, interfacial properties, and durability without altering their bulk structure. By delivering ions, radicals, photons, and excited species directly at ambient conditions, we selectively modify surface functional groups, graft new chemical motifs, and create nanoscale texturing that enhances adhesion, wetting behavior, and environmental resilience.
These nonequilibrium plasmas introduce oxygen-, nitrogen-, or carbon-containing functionalities, remove organic contaminants, and activate surfaces for coating adhesion, polymer grafting, and hybrid composite formation. Unlike vacuum-based plasma systems, our atmospheric-pressure platforms treat complex geometries, porous substrates, and architected bio-materials with minimal thermal load, making them uniquely suited for sustainable feedstocks, bio-derived composites, and living or bio-grown materials.
Plasma-modified wood and mycelium systems open pathways to structurally robust, chemically tailored, and environmentally responsive materials for architected composites, coatings, packaging, and built-environment applications. By combining renewable substrates with advanced surface processing, we create bio-based systems that are engineered for durability, adhesion, and functional performance — bridging nature-derived materials with modern manufacturing.
Students: Rowan Ellis
Optical Emission Spectroscopy & Plasma–Liquid Chemistry
Optical Emission Spectroscopy (OES) enables real-time insight into the reactive species landscape generated when aerosolized liquids are injected into an atmospheric-pressure plasma jet (APPJ). As micron-scale droplets enter the nonequilibrium discharge, they evaporate, fragment, and react with energetic electrons, radicals, and photons. OES captures the resulting electron-impact species, reactive oxygen and nitrogen species (RONS), and transient intermediates — including OH*, N₂*, NO*, H*, and O* — that drive chemistry at the aerosol–plasma–liquid interface.
By tracking emission signatures as a function of precursor identity, droplet loading, injection geometry, and plasma power, we map how aerosol introduction perturbs energy partitioning, ionization dynamics, and reactive flux into the liquid phase. These optical fingerprints reveal how plasma–generated species initiate bond scission, oxidation, reduction, polymerization, and crosslinking in solution-borne precursors, ultimately shaping bonding motifs, defect chemistry, and nanostructure evolution in plasma-processed materials.
Through this approach, OES connects gas-phase plasma physics to liquid-phase chemistry and solid-state material formation, providing mechanistic control over aerosol-mediated APPJ synthesis pathways — a key capability for designing hybrid networks, doped carbon materials, and complex oxide architectures with tunable functionalities.
Students: Wilson Congdon