(4fg) The Design of Platinum-Based Bimetallic Catalysts for the Hydrodeoxygenation of Carboxylic Acids

My research interests are solidly shaped by coupling my experiences growing up in crude oil-producing Nigeria with the research gaps that my knowledge has now elucidated in the field of computational heterogeneous catalyst design for renewable fuel production. I am deeply in favor of all the concerted efforts, especially in recent times, put in place to seek realistic alternatives to fossil fuel oil. The exploration and usage of fossil fuel oil leaves such devastating and lasting effects that require extended periods and significant financial outlay to clean up. Renewable oil has the most potential because it is the best substitute for fossil fuel oil in our internal combustion engines and is a more carbon-neutral alternative. However, generating a gallon of usable biofuel can cost up to five times as much as producing an equivalent amount of fossil fuel oil. The majority of this expense is related to the upgrading of bio-oil by lowering the high oxygen content (~40 wt%) to acceptable levels for carbon-based fuels (2 wt%). The significant oxygen content results in low heating value, low miscibility with other fuels, low energy density, increased polarity, instability, and corrosiveness. Thus, the overarching goal of my research is to computationally design catalysts that decrease biofuel production costs.

The most promising route for sustainable, renewable fuel production is via upgrading biomass-derived chemicals with bimetallic catalysts. However, such bimetallic catalysts often reconstruct and lose performance upon exposure to reaction environments. The gaps in designing bimetallic catalysts include inadequate connections between reaction conditions, surface reconstruction, and chemical insights into the synergy between constituent metals. Hence, there is a critical need to zoom down to nanoscale levels to characterize the interactions between relevant adsorbates and the metal constituents and connect them to the dominant surface features formed under different reaction environments. All of these nanoscale investigations then need to be scaled to macroscale levels to obtain usable metrics to adequately understand, gauge, predict, and tune catalytic reconstructions and performance. Employing solid theoretical concepts to translate fundamental nanoscale insights into macroscale, real-world results have potential applications to the general design of heterogeneous bimetallic catalysts for wide ranges of important chemical reactions. These approaches will advance the production of biofuels toward viable commercial levels.

Overall, whether it is focusing on computational research or foraying into experimental designs to investigate chemical processes, the common denominator in my research interest is the creation of models that mimic reality as much as possible. Such models smartly incorporate components that address concerns that often lead to discrepancies in the results from the models and reality, all in a quest to sustainably produce fuels and valuable chemicals.

Awards and Successful Proposals

• Frontera Computational Science Fellowship Award, $34,000 in stipend, $12,000 in tuition allowance, and 50,000 CPU hours awarded, 2024-2025.
• Catalysis and Reaction Engineering (CRE) Division Student Travel Award for the 2023 Annual AIChE Meeting, $400 awarded, 2023.
• Stevens Graduate Conference Funding for the 2023 Annual AIChE Meeting, $1,500 awarded, 2023.
• Kokes’ Award for the 28th North American Meeting (NAM) of the Catalysis Society, ~$1,700 in hotel fees awarded, 2023.
• User Proposals at Center for Nanoscale Materials at Argonne National Lab, ~1.45 million CPU hours awarded, 2022-2024.
• User Proposals at Center for Functional Nanomaterials at Brookhaven National Lab, ~430,000 CPU hours awarded, 2023-2024.
• Provost Doctoral Fellowship Award from Stevens Institute of Technology, $63,206 yearly awarded, 2021.

Selected Publications

• Omoniyi, A.; Hensley, A.J.R., Coverage and Facet Dependent Multiscale Modeling of O* and H* Adsorption on Pt Catalytic Nanoparticles, Phys. Chem. C., 2024, 128, 7073-7086.
• Pipitone, G.; Hensley, A.J.R.; Omoniyi, A.; Zoppi, G.; Pirone, R.; Bensaid, S., Unravelling Competitive Adsorption Phenomena in the Catalytic Valorization of Wastewater Streams: An Experimental and Theoretical Study, Chem. Eng., 2024, 482, 148902.
• Furrick, I.; Omoniyi, A.; Wang, S.; Robinson, T.; Hensley, A.J.R., Integration of Facet-Dependent, Adsorbate-Driven Surface Reconstruction into Multiscale Models for the Design of Ni-Based Bimetallic Catalysts for Hydrogen Oxidation, ChemCatChem, under review 2024.
• Garzon, A.; Wang, S.; Omoniyi, A.; Tam, L.; Che, F.; Hensley, A.J.R., Temperature and Pressure Driven Functionalization of Graphene with Hydrogen and Oxygen via Ab Initio Phase Diagrams, Surf. Sci., under review 2024.
• Omoniyi, A.; Bensaid, S.; Pipitone, G.; Hensley, A.J.R., Impact of Intermolecular Interactions in the Adsorption of Carboxylic Acids on Pt(111), in-preparation, 2024.
• Omoniyi A.; Vadehra M.; Thompson C.; Braslavets S.; Duggan S.; Hensley A.J.R., A Comprehensive Analysis of the Process, Economics, and Business Model of Converting Used Cooking Oil to Biodiesel in the Northeastern United States, in-preparation, 2024.

Research Experience

I currently work on the design of bimetallic catalysts for biofuel production using computational chemistry and high-performance computing. My focus is on filling the gaps in the understanding of how reaction conditions, synergistic nanoscale interactions between metal constituents, and adsorbate-driven surface reconstructions are connected for bimetallic catalyst systems. Now finishing up my third year of Ph.D. research, I possess the required skills, understanding, and expertise in computational chemistry techniques to make such investigations.

Hitherto, I have used multi-scale modeling to characterize the coverage-dependent behavior of adsorbates on platinum and nickel catalysts, making use of high-performance parallel computers at Argonne and Brookhaven National Laboratories. This is demonstrated across three major projects. First, I worked with experimental collaborators, computationally investigating competitive adsorption effects for carboxylic acid reactions on platinum catalysts. By accurately recreating a computational model of the experimental realities, we were able to understand the preferential reaction of some carboxylic acids instead of others on platinum. Second, I computationally quantified the contributions of adsorbate-surface and adsorbate-adsorbate interactions to the coverage and configuration of oxygen and hydrogen, key adsorbates in a range of reactions, on multifaceted platinum nanoparticles. By incorporating coverage effects, I was able to benchmark our models to published experiments for desorption temperatures, vibrational frequencies, and most dominant coverages for a wide range of temperatures and pressures. Third, various dopants in nickel-based bimetallic catalysts were investigated to substitute the efficient and expensive platinum catalyst for the hydrogen oxidation reaction. This study used models that replicated reality much more closely through multifaceted investigations and simultaneous forays into the stability of bimetallic systems at various reaction conditions (e.g. temperature, pressure, reactant concentrations). Overall, my imprint on the field is creating accurate computational models that encompass numerous realistic worries, to produce experimentally reproducible results.

Teaching Interests

Globally, society is highly focused on new science and technologies and rightfully so, but my experience has shown me that lesser emphasis is being placed on deeply learning, understanding, and applying foundational concepts within chemical engineering. For example, while teaching classes such as thermodynamics, reactor design, and fluid mechanics as a graduate assistant in Nigeria and as a teaching assistant in the US, I have seen an alarming inadequacy among students in the fundamental understanding of key building blocks required for advanced, new science and technology to build upon. Starting from my local teaching community, I would love to ensure that these bases are adequately covered with my teaching/assistance with any of the aforementioned courses. I intend to administer these familiar concepts with modern and real-world comparisons to ground such understanding. Promoting active learning, technology incorporation, and a very open channel for students and even fellow faculty members is my suggestion of a three-pronged approach to achieving this.

With the foundational courses covered consistently and after a few years down the line, one of the ideas about new science/missing bits of the senior/graduate chemical engineering curriculum I have is the implementation of an introductory coursework to computational chemistry. Quantum chemistry tenets, statistical mechanics, and solid-state physics sections will constitute the syllabus for the course.

I am passionate about teaching because I live for the moment the lightbulb comes alive for the student. I strongly believe that ensuring these moments happen more often is the solution to keeping the ‘short attention span’, modern students engaged with above-adequate mastery of the important fundamentals.

Service Experience

I am passionate about easing the lives of others, especially those of determined individuals who travel far from home to pursue world-class graduate education. Leaving all of one’s life behind to try to acclimatize to a new educational system is a handful that can leave one alone and frustrated, especially with the lack of required help/information. This is why instituted student groups such as the African Student Association (ASA) at Stevens Institute of Technology where I am currently the secretary of this body are very important. Outside of the official role too, I belong to various volunteer social groups such as Nigerians in the US (NiUS) and NJ Hudson County Soccer, where the aim remains to help satisfy the social needs of these budding scientists and provide prompt aid in terms of mentorship, advice, informational tips, etc. These efforts are in a quest to give back and ensure no African in the area experiences such a drastic culture shock that I experienced in my early days.