Don’t Dis Dissertations: Energetics of Catalytic Intermediates on Nickel(111) by Calorimetry

Dissertations offer value beyond their actual content, which itself can be quite useful. For one thing, they can alert you to emerging talent that can help you achieve your objectives.

Here is an example that I found as the result of an email alert …

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Energetics of Catalytic Intermediates on Nickel(111) by Calorimetry: Empirical Trends and Benchmarks for Quantum Theory
Spencer J. Carey
Dissertation (Ph.D.)--University of Washington, 2018
Our society depends on the use of catalysts for the manufacture of 90% of chemical industry products, for the mass production of fertilizers that grow our food supply, for the synthesis of the fuels that drive our transportation systems, and for the purification of pollutants, such as those produced by car engines. With this utility comes a huge investment of effort to understand the fundamental science behind catalysts and to improve their efficiency, durability, and selectivity. It is also important to be able to design new catalysts for changing feedstocks (e.g., replacement of coal and petroleum with methane, biomass and other renewables). In the last fifty years, new methods to study catalytic processes have been developed, which in turn resulted in an explosion of research studies that address the fundamental questions in the catalysis field. Quantum mechanical calculations using Density Functional Theory (DFT) are one such technique that has become invaluable in studying catalysts. This method allows for the efficient and inexpensive prediction of catalyst mechanisms and kinetics, structure-function relationships, and even in screening for new, more effective catalysts. However, the accuracy of these predictions depends upon reliable energetic information of adsorbed catalytic reaction intermediates, such as their heats of formation and bond enthalpies to the surface. The energies of adsorbed intermediates and transition states on surfaces are the key factors that determine the effectiveness of any given catalyst. The results of this dissertation show that the energy accuracy of these DFT methods is far less than desirable, and it provides many experimental benchmark energies that will be useful for the development of more accurate DFT functionals. This dissertation is part of a decades-long effort by our research group to compile a large database that contains the heats of formation of many adsorbates on different model catalyst surfaces. This database aims to provide valuable benchmarks that theorists can use to improve DFT functionals. To expand this database, our research group uses Single-Crystal Adsorption Calorimetry (SCAC), the only method able to directly measure the binding energies of adsorbates to model surfaces. My research is focused on expanding the adsorbate bond energy database in the areas that it is lacking. Specifically, previous to this dissertation, this database only included adsorbed molecular fragments on one metal surface, Pt(111) and only included aromatic molecules on one non-noble metal surface, again Pt(111). We have extended both of these classes of adsorbates to their energies on the Ni(111) surface, with comparisons between the energies on Pt(111) versus Ni(111) which help explain some of the differences in catalytic properties of Pt versus Ni. In this thesis, SCAC is used to study the molecular adsorption of phenol and benzene on both Pt(111) and Ni(111). Both benzene and phenol are aromatic, and their energetics are heavily influenced by van der Waal forces. SCAC is also used to study the dissociative adsorption of methyl iodide on Ni(111) to produce adsorbed methyl and iodine adatoms and the dissociative adsorption of methanol on O-precovered Ni(111) to produce adsorbed methoxy and hydroxyl. Adsorbed methyl and methoxy are important molecular fragments that are catalytic intermediates in several industrial processes. Finally, a new equation is derived that relates the sigma bond enthalpies of several molecular fragments to both Ni(111) and Pt(111). This trend allows predictions of the sigma bond enthalpies of other small molecular fragments to transition metal surfaces.
Full text source: https://digital.lib.washington.edu/researchworks/handle/1773/42241
source: https://digital.lib.washington.edu/researchworks/handle/1773/42241
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FREE DISSERTATIONS

“You're searching, Joe, for things that don't exist; I mean beginnings. Ends and beginnings -- there are no such things. There are only middles.” Robert Frost (American poet, 1874-1963)

ProQuest (http://www.proquest.com/) serves as a clearinghouse for dissertations produced by graduate students from all over the U.S.  Most of the ProQuest dissertations must be purchased.  However, some of them are available at no charge.

Use the link below to search and retrieve all open access dissertations:
http://pqdtopen.proquest.com

For example, searching the ProQuest open access database for hydrocarbon results in several hits, among which is …

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Recycling Carbon Dioxide into Sustainable Hydrocarbon Fuels: Electrolysis of Carbon Dioxide and Water
by Graves, Christopher Ronald, Ph.D.  Columbia University. 2010: 282 pages.
The purpose of this work was to develop critical components of a system that recycles CO2 into liquid hydrocarbon fuels. The concept is examined at several scales, beginning with a broad scope analysis of large-scale sustainable energy systems and ultimately studying electrolysis of CO2 and H2O in high temperature solid oxide cells as the heart of the energy conversion, in the form of three experimental studies. The contributions of these studies include discoveries about electrochemistry and materials that could significantly improve the overall energy use and economics of the CO2-to-fuels system.
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TIP: Remember that there are lots more dissertations that are NOT open access.  If you don’t find what you’re looking for in the open access pool, try searching for the dissertations in the restricted pool.

Searching ProQuest open access for desulfurization, for example, will result in 0 hits.  That just means there are no dissertations listed in the ProQuest open access database on the topic of desulfurization. Searching the complete ProQuest database would yield much different results.