About

Elizabeth Elacqua is an Associate Professor of Chemistry and Weinreb Family Early Career Professor at Penn State University. Her research interests include organic polymer synthesis, catalysis, materials, and supramolecular chemistry. She has a background in supramolecular and solid-state organic synthesis, with a Ph.D. from the University of Iowa and postdoctoral experience at New York University focusing on polymer synthesis and self-assembly. Her work has contributed to the development of advanced materials through innovative polymerization techniques and the design of nanothreads, as well as exploring the role of confinement in catalysis and photoredox processes. Elacqua has received numerous honors, including the NSF CAREER Award, Alfred P. Sloan Research Fellowship, and awards from the American Chemical Society for her contributions to materials research and organic chemistry.

Research topics

• Chemistry
• Organic chemistry
• Crystallography
• Biochemistry
• Materials science
• Cell biology
• Stereochemistry
• Computational biology
• Genetics
• Biology
• Biophysics
• Optics
• Polymer chemistry
• Composite material

Selected publications

• An Electrochemical Design for a General Catalytic Carboxylic Acid Substitution Platform via Anhydrides at Room Temperature: Amidation, Esterification, and Thioesterification

  Organic Letters · 2025-02-14 · 8 citations

  article

  An original concept for catalytic electrochemical dehydration has enabled a suite of acid substitutions, including amidation, esterification, and thioesterification, through a linchpin anhydride formed in situ. By avoiding stoichiometric dehydrating agents, this method addresses a leading challenge in organic synthesis and green chemistry. It also proceeds without acid additives at room temperature, accesses a diverse range of product structures, is easily scaled, and enabled the first example of catalytic peptide coupling at room temperature.

  PublisherDOI

• Cyclobutane-linked Nanothreads through Thermal and Photochemically Mediated Polymerization of Cyclohexadiene

  ChemRxiv · 2025-05-19 · 1 citations

  preprintOpen accessSenior author

  Carbon nanothreads are a rapidly growing class of 1D nanomaterials with sp3-hybridized diamond-like backbones. They are typically synthesized through pressure-induced polymerizations of aromatics, resulting in diverse structures and functionalities. Aside from precursor selection, there are limited means to control reaction pathway or polymerization outcome. Analogous to selection rules that govern outcomes in molecular chemistry, we investigated thermally and photochemically mediated pressure-induced polymerizations of 1,4-cyclohexadiene and explored the resultant products. Thermally mediated polymerization of 1,4-cyclohexadiene yields a crystalline product; yet identification of the backbone architecture is complicated by the product’s less ordered packing in which only two Friedel pairs are observed. Support for cyclobutane-based structures is present when comparing experimentally-obtained data to computed structures, yet further evidence suggesting elliptical cross-sections consistent with anti-cyclobutanes is obtained when comparing experimental data obtained from a Paris Edinburgh (PE) synthesis. In contrast, the recovered product obtained from the photochemically mediated polymerization exhibits different d-spacings and is consistent with simulations that support a single pathway toward highly elliptical syn-cyclobutane-linked nanothreads. These results suggest that photochemistry can enable reaction selectivity in nanothread synthesis.

  PublisherOA PDFDOI

• Recyclable iridium-containing copolymers for homogeneous photoredox catalysis

  Polymer Chemistry · 2025-01-01

  articleOpen accessSenior authorCorresponding

  We present iridium polypyridyl-based-PMMAs that catalyze a broad swath of homogeneous photoredox-mediated transformations, while also enabling recyclable and sustainable catalysis.

  PublisherDOI

• Cooperative Photoredox Catalysis Under Confinement

  Chemistry - A European Journal · 2025-03-08 · 3 citations

  articleOpen accessSenior authorCorresponding

  Photoredox catalysis has emerged as a potent means to conduct synthetic chemistry. Leveraging light to achieve challenging organic transformations has led to many developments, both of fundamental and industrial nature. Despite their potency, photoredox processes are inherently diffusion controlled, which can limit their ability to enable both reactivity and selectivity. Relevant to this is the idea of colocalizing cocatalysts in architectures that enable spatial proximity, promoting 'catalysis under confinement.' In this Concept review, we summarize recent designs and advancements using well-defined heterogeneous and homogeneous frameworks that enable dual photoredox catalysis, such as metal-organic frameworks, heterogeneous organic polymeric systems, and single-chain polymer nanoparticles (SCNPs). These advances generally stem from the material's inherent ability to enforce catalyst communication, typically resulting in expedient radical, electron, or energy transfer that accelerates reactivity. Whereas heterogeneous systems are comprehensively investigated, the design space arising from the modularity and versatility of a SCNP is quite large making the recyclable platform an intriguing candidate to investigate for confinement-enabled photoredox catalysis. We expect that both heterogeneous and homogeneous platforms systems detailed herein will continue to exhibit superior performance, while underscoring the importance of confinement to tackle diffusion-limited reactions.

  PublisherOA PDFDOI

• Cyclobutane-linked nanothreads through thermal and photochemically mediated polymerization of cyclohexadiene

  Polymer Chemistry · 2025-01-01 · 1 citations

  articleOpen accessSenior author

  We present the pressure-induced polymerization of 1,4-cyclohexadiene, wherein thermal methods may access multiple reaction pathways. In contrast, light enables solely cyclobutane-based nanothreads to arise from a single viable reaction pathway.

  PublisherOA PDFDOI

• High-Pressure Synthesis of Carbon Nanothreads from Polycyclic Aromatic Hydrocarbons

  ACS Materials Au · 2025-12-23 · 1 citations

  articleOpen accessSenior authorCorresponding

  Carbon nanothreads are one-dimensional sp3-hybridized polymers that have been theorized to exhibit new mechanical, thermal, or electronic properties. When derived from polycyclic aromatic hydrocarbons, nanothreads with thicker diameters emerge, which may promote higher ultimate strengths and/or bending moduli. In this contribution, we investigate the thermally mediated polymerization of naphthalene and pyrene under uniaxial pressure. Both PAHs undergo successful polymerizations, affording crystalline solids with distinctly different interplanar spacings (dNap = 7.77, 6.64, and 6.24 Å; dPy = 8.81, 8.37, and 7.33 Å). The application of heat resulted in the reduction of maximum pressures (at least 8 GPa for naphthalene and at least 4 GPa for pyrene), with a more well-defined diffraction pattern being obtained in the polymerization of pyrene. Spectroscopic analysis supported the formation of predominantly C(sp3)-hybridized extended carbon materials, consistent with simulated crystalline nanothreads without cross-linking.

  PublisherDOI

• Rational Approaches toward the Design and Synthesis of Carbon Nanothreads

  Accounts of Chemical Research · 2025-05-20 · 6 citations

  articleSenior authorCorresponding

  ConspectusCarbon-based materials─often with superlative electronic, mechanical, chemical, and thermal properties─are often categorized by dimensionality and hybridization. Most of these categories are produced in high-temperature conditions that afford equilibrium-dictated structures, but limit their diversity. In contrast, an emerging class of one-dimensional (1D) carbon materials, coined nanothreads, are accessible through kinetically controlled solid-state reactions of small multiply unsaturated molecules. While abundant in molecular organic synthesis, exerting kinetic control over reactivity is a revolutionary approach to access dense carbon networks. Owing to their internal diamond-like core, these materials are calculated to span a wide range of mechanical and optical properties, with the introduction of functional groups and/or heteroatoms leading to tailorable band gaps and the potential to access electronic states that are not featured in traditional polymers or nanomaterials. Accessing these properties requires the ability to precisely control solid-state molecular reaction pathways, chemical connectivity, and heteroatom/functional group density. Carbon nanothreads are often synthesized through the pressure-induced polymerization of aromatic molecules (e.g., benzene, pyridine, and thiophene) upon compression to 23–40 GPa. While the high pressures required to achieve these crystalline materials often preclude making synthetically viable quantities of product, the use of lessened aromatic reactants, along with light and/or heat, enables more mild reaction pressures. Success to date in forming nanothreads from diverse reactants suggests that physical organic principles govern the reaction, along with topochemical relationships, enabling the emergence of a new field of carbon chemistry that combines the control of organic chemistry with the range of physical properties only possible in extended periodic solids.In this Account, we describe our efforts to rationally synthesize carbon nanothreads with desired structures and present our approaches to dictate reactivity in the organic solid state that enable the formation of crystalline 1D carbon materials. In particular, we focus on the principles being pursued by our group to expand the chemical diversity of materials being accessed, while highlighting efforts that both enhance selectivity over reaction pathways and reduce pressure requirements for polymerization. We begin by leveraging starting materials with lessened or no aromaticity (relative to benzene) to design new backbones while enabling lower pressures such as 15–20 GPa to achieve nanothread formation. Next, we discuss efforts to utilize photochemical activation as a means to dictate the reaction pathway and/or affect the mechanism while also achieving ordered crystalline solids at reduced pressures. Lastly, we highlight efforts to demonstrate kinetic control in solid-state reactions by leveraging supramolecular chemistry (e.g., aryl/perfluoroaryl interactions, hydrogen bonds, π-π stacking) to preorganize starting materials into polymerizable molecular stacks. The resultant design principles provide multiple opportunities to attain previously inaccessible sp3-rich 1D polymeric carbon nanomaterials with unique structures and properties from widely available small molecules. Moreover, the kinetic control provided in the organic solid state enables a priori functionalization and the design of a rich diversity of materials with emergent properties in stark contrast to many well-developed carbon materials.

  PublisherDOI

• Visible-light-mediated Diels–Alder reactions under single-chain polymer confinement: investigating the role of the crosslinking moiety on catalyst activity

  Polymer Chemistry · 2024-01-01 · 13 citations

  articleOpen accessSenior authorCorresponding

  Macromolecular scaffolds are rapidly emerging in catalysis owing to the ability to control catalyst placement at precise locations. This spatial proximity allows for enhanced catalyst activity that may not be observed using small molecules. Herein, we describe a triphenylpyrylium (TPT)-based visible-light active single-chain polymer nanoparticle (SCNP) that facilitates the radical cation [4 + 2]-cycloaddition. We find that the catalytic activity is highly dependent on the styrylarene comonomer used, wherein it can act as a redox mediator under confinement, increasing the catalytic turnover (TON) by up to 30 times in comparison to free TPT in solution. Mechanistic studies indicate that TPT excited states are quenched by the acene, with the resultant radical cation formed from naphthalene-based SCNPs able to proceed in oxidizing the dienophile in the elementary step of the reaction, while leading to near quantitative yields of the cycloadduct. The TPT-SCNP demonstrates enhanced photocatalyst efficiency compared to molecular TPT, and is able to be recycled and reused in three iterations of the reaction prior to decreased performance from photobleaching. Our results overall suggest that the confined nature of the SCNP and spatial proximity of acene-based pendants enforces their participation as cocatalytic redox mediators that impart enhanced photoredox catalysis under confinement.

  PublisherOA PDFDOI

• Cyclobutane-linked Nanothreads through Thermal and Photochemically Mediated Polymerization of Cyclohexadiene

  ChemRxiv · 2024-07-19

  preprintSenior author

  Carbon nanothreads are a rapidly growing class of 1D nanomaterials with sp3-hybridized diamond-like backbones. Most nanothreads are synthesized through the pressure-induced polymerization of aromatics, resulting in diverse structures and functionalities. Aside from precursor selection, there are currently limited means to control nanothread reaction pathway or polymerization outcome. Analogous to selection rules that govern outcomes in small molecule chemistry, we investigated both thermally and photochemically mediated polymerizations of skipped and conjugated dienes (1,3- and 1,4-cyclohexadiene) under high pressure and explored the resultant product selectivity. For 1,3-cyclohexadiene, both approaches yield largely amorphous products owing to competing reaction pathways. Thermally mediated polymerization of 1,4-cyclohexadiene yields a crystalline product; however, the identification of the backbone composition is consistent with multiple different reaction pathways being accessible. While support for cyclobutane structures is present, comparison to the simulated structures suggests multiple products are obtained from the thermal polymerization of 1,4-cyclohexadiene. In contrast, the recovered product obtained from photochemically mediated polymerization of the skipped diene has different d-spacings and is consistent with simulations that support a single reaction pathway toward cyclobutane-linked nanothreads. These results suggest that photochemical activation can enable product selectivity in nanothread synthesis.

  PublisherDOI

• Diarylation encodes precision for polyolefins

  Nature Synthesis · 2024-08-21 · 1 citations

  article1st authorCorresponding
  PublisherDOI

Recent grants

• CAREER: Nanoreactors for Dual Catalysis Under Polymer Confinement

  NSF · $677k · 2021–2026

Frequent coauthors

• Stephen J. Koehler

  Virginia Tech

  89 shared

• Manas Bandyopadhyay

  Indian Institute of Engineering Science and Technology, Shibpur

  81 shared

• Tianning Diao

  New York University

  81 shared

• N. D. Zelinsky

  Moscow Power Engineering Institute

  81 shared

• Richard J. Hooley

  University of California, Riverside

  81 shared

• Cyrille Sabot

  Normandie Université

  81 shared

• Qian Liu

  Chinese Academy of Sciences

  81 shared

• Dorothea Anthony

  University of Wollongong

  81 shared

Education

• Doctor of Philosophy, Chemistry

  University of Iowa

  2012

• Bachelors of Science, Chemistry and Biology

  Le Moyne College

  2006

Awards & honors

• Rustum and Della Roy Innovation in Materials Research Award…
• American Chemical Society, Division of Polymeric Materials S…
• American Chemical Society, Division of Organic Chemistry (OR…
• Alfred P. Sloan Research Fellow (2021)
• NSF CAREER Award (2021)