Projects

Research Vision: Transforming Energy Conversion through Reactive Nanomaterials

My PhD research addresses the fundamental challenges of using nanostructured materials for chemical energy conversion. While nanomaterials offer theoretical advantages in energy density and reactivity, their practical application is hindered by inherent interfacial and thermal barriers.

In my work, I focus on two primary bottlenecks that currently limit the efficiency of reactive nanomaterials

Bypassing Diffusion Kinetic Barriers: Most nanometals naturally form a native oxide shell. This layer acts as a physical barrier, slowing down the diffusion process and preventing the core metal from reacting efficiently with oxidizers. I develop strategies to functionalize these surfaces to enhance reactivity without compromising stability.

Mitigating Thermal Agglomeration & Sintering: Nanoparticles possess high surface energy, making them prone to reactive sintering at elevated temperatures. This loss of surface area often occurs before the intended reaction can even begin. My research involves designing nanostructures that maintain their architecture and reactivity even under extreme thermal environments

Impact

By understanding these structure-property-activity relationships, my research enables the creation of tailorable high-energy materials for applications ranging from advanced propellants to localized power generation.

Projects I have led

Method 1: Matrix Based Functionalization

Summary: Engineering the surrounding environment (polymers/oxidizers) to drive gas generation and interfacial contact.

Project 1: Using Gas-Generating Binders to Prevent Sintering

Project 2: Embedding Nanoparticles Inside Oxidizer Matrix to Drive Interfacial Reaction

Project 3: Using a Polymer Binder to Etch/Remove Native Oxide Shell of a nanoparticle

Method 2: Particle Surface Engineering

Summary: Modifying the nanoparticle itself to bypass oxide shells via hydrogenation and coatings.

Project 4: Plasma Treatment to Hydrogenate Nanoparticles

Project 5: In Situ TEM Oxidation and Diffusion Kinetics Study

Project 6: Coating the surface of Magnesium Nanoparticle to Alter the Reaction Pathways

Project 1: Using Gas Generating Binders to Prevent Sintering

Designed and optimized a spray drying synthesis process which binded nano metals and oxidizers together. The spray drying system could scale up the composite production up to ~160x while maintain precise control over structures and properties.
With higher production of this composite led the way to fabricate 3D printed propellant films

Impact: The gas generation from the polymer decomposition prevented particle agglomeration and complete combustion. The reaction rate in constant pressure combustion cell could be increased by 700%

3D Printed stick with a hierarchical structure ( nano, micro, macro)

Project 2: Embedding Nanoparticles Inside Oxidizer Matrix to Drive Interfacial Reaction

Using the spray drying approach, I designed and optimized a synthesis approach to incorporate Boron (B) nanoparticles inside a crystalized Ammonium Perchlorate oxidizer Matrix into a micron architecture particle.

Impact: The reactivity could be increased by 150%. I designed an In Situ TEM experiment and studied interphase reaction, and from atomic scale imaging revealed the significant in situ formation of BN, which is normally overlooked for Boron Combustion studies.

In situ TEM heating experiment on the functionalized Boron/AP System

Project 3: Using a Polymer Binder to Etch/Remove Native Oxide Shell of a nanoparticle

Designed a synthesis approach to functionalize Aluminum particles inside Polyvinylidene fluoride (PVDF) matrix. Upon decomposition of PVDF produces hydrogen fluoride gas which can etch native oxide layer of Aluminum and increase the reactivity.

Impact: Aluminum could be made come out of the oxide shell at low temperature, currently studying the interface reaction mechanism

Alumnium Particles embedded inside PVDF structure

Project 4: Plasma Treatment to Hydrogenate Nanoparticles

Led a collaborative project where we hydrogenated Magnesium nanoparticles utilizing non thermal plasma and this hydrogenation layer can passivate the nanoparticles.
Utilized various material characterization techniques including in situ X-ray photoelectron spectroscopy, time of flight mass spectrometer, Thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC) to understand the reaction mechanism.

Impact: The reactivity could be enhanced by 900% and lowered the ignition temperature by ~200 °C. I found that upon hydrogen desorption leaves behind a fresh magnesium surface without a native oxide shell and can immediately undergo oxidation reaction.

My Proposed Reaction Mechanism

Project 5: In Situ TEM Oxidation and Diffusion Kinetics Study

Developed newly procured in situ Environment Cell TEM workflow to study oxidation and diffusion kinetics of Magnesium and hydrogenated Magnesium under controlled oxygen environments.
Developed MATLAB codes to study the diffusion kinetics and mechanism from real time image sequences.

Impact: From time resolved image sequences, I quantified outward diffusion fluxes and compared different systems. For example, I found hydrogenation increased the outward diffusion flux of Mg by approximately an order of magnitude relative to unmodified Mg nanoparticles. Measurement of oxide shell growth provided additional insight into oxidation kinetics and how it can be tuned through composition and architecture.

Diffusion/Oxidation Kinetics study utilizing in situ TEM experiment

Project 6: Coating the Surface of Magnesium Nanoparticle to Alter the Reaction Pathways

Led this collaborative work to functionalize the surface of Magnesium nanoparticle with nickel coating to employ a core-shell structure. This nickel coating can undergo interfacial alloying exothermic reaction with magnesium elevating the particle temperature and accelerate outward Magnesium transport.
Tuned the ignition temperature based on the thickness of the Nickel coating layer, Could decreased the ignition temperature up to ~200 °C by optimizing the thickness

Proposed Reaction Mechanism

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