Title : Ionic liquid phases on copper nanoparticles: DFT insights and modulation of the electronic environment for catalysis
Abstract:
A novel series of Supported Ionic Liquids (SILPs) based on triazolium core were meticulously synthesized and harnessed as catalysts for facilitating the N-arylation of aryl halides with anilines. The synthesis procedure involved the adept chemical modification of triazoles through copper-catalyzed azide-alkyne cycloaddition. he ensuing comprehensive surface characterization divulged a robust correlation between the volume of the triazolium cation and the textural attributes of the SILPs. Notably, Scanning Transmission Electron Microscopy (STEM) unveiled the well-dispersed arrangement of copper nanoparticles (Cu NPs) on the SILPs, presenting diameters ranging from 3.6 to 4.6 nm. This variance in size was contingent upon the specific triazolium cation employed.
Additionally, X-ray Photoelectron Spectroscopy (XPS) findings illuminated the manipulable nature of the Cu(0)/Cu(I) ratio through the electronic density of triazolium substituents. Through a combination of XPS and computational analysis, mechanistic insights were acquired, elucidating the pathways that stabilize Cu NPs. Particularly intriguing, triazolium ring-bonded electron-rich groups were inclined towards cation adsorption pathways, whereas less electron-rich groups favored anion adsorption pathways. Significantly, Cu@SILP composites possessing electron-rich groups demonstrated remarkable efficacy in the C-N Ullmann coupling reaction, underscoring their function as electron reservoirs that promote N-arylation via oxidative addition. This study highlights the fundamental role of triazolium-based SILPs in delineating the nature of active sites on Cu NPs surfaces, thereby offering promising avenues for innovative applications in the realm of confined and stabilized metal nanoparticle catalysis.
Furthermore, an exhaustive exploration into the interplay between Supported Ionic Liquid Phases (SILPs) incorporating triazole and copper nanoparticles was meticulously undertaken through Density Functional Theory (DFT) calculations. This study encompassed three distinct triazolium cations (T1+, T2+, and T3+) alongside four different anions (I−, BF4−, PF6−, and NTf2−) for the assembly of Cu@SILP complexes. Notably, the simulations unveiled a pronounced preference for anion adsorption onto copper nanoparticles, surpassing cation adsorption. The interaction between Cu@SILP complexes was intricately governed by coordinate covalent bonds, subject to modulation through chemical substitutions at positions N1 and N3 on the triazole ring, encompassing electron-rich groups. Noteworthy, the Cu@(I)SILP1 (R: Bn and Ph) complex exhibited the most potent adsorption, attributed to its elevated electron-rich triazole characteristics and substantial SILP adsorption onto the Cu surface (5.18 eV). Leveraging surface modifications, the manipulation of complex properties became feasible, wherein anions induced coarse adjustments while precise fine-tuning was accomplished via chemical modifications of the triazolium ring. This dual-pronged investigation furnishes invaluable insights into the tailored design and manipulation of triazolium-based SILPs, ultimately leading to catalytic augmentation and promising applications within Cu nanoparticle interactions.
Audience Take Away:
- Explain how the audience will be able to use what they learn?
The audience will gain a comprehensive understanding of the synthesis, characterization, and applications of supported ionic liquids (SILPs) based on triazolium in catalytic processes involving copper nanoparticles. They will acquire insights into the relationship between the triazolium cation's characteristics and the resulting textural properties of SILPs, which can guide future material design and synthesis. Furthermore, attendees will learn about the mechanistic insights derived from XPS and computational analysis, offering a deeper comprehension of the pathways that stabilize copper nanoparticles and their catalytic behavior.
- How will this help the audience in their job?
Professionals in the catalysis and materials science field will benefit by incorporating the knowledge gained into their research and development efforts. They can apply the findings to design more effective catalysts, tailor active sites for specific reactions, and optimize synthesis processes. Understanding electron-rich groups' role in catalytic reactions will enable them to engineer more efficient and selective catalysts for various chemical transformations.
- Is this research that other faculty could use to expand their research or teaching?
The presented research holds substantial potential for other faculty members in the catalysis and materials science domain to expand their research and teaching. The insights into the design, synthesis, and characterization of novel SILPs can inspire new avenues of exploration. Additionally, the mechanistic understanding of catalyst stabilization and catalytic pathways could enrich teaching curricula and enhance students' comprehension of catalytic processes.
- Does this provide a practical solution to a problem that could simplify or make a designer’s job more efficient?
The research offers practical solutions for designing and optimizing catalysts using tailored SILPs and copper nanoparticles. By understanding the interplay between electron-rich groups, triazolium cations, and copper nanoparticles, designers can fine-tune catalysts to achieve higher efficiency and selectivity, simplifying the catalyst development process for various chemical reactions. This material design could be applied to modulate the chemical reactivity of other metal nanoparticles (MNPs), expanding the variety of targeted reactions.
- Will it improve the accuracy of a design or provide new information to assist in a design problem?
Yes, the research introduces new insights that can significantly improve the accuracy of catalyst design. Understanding how electron-rich groups influence cation and anion adsorption pathways on copper nanoparticles provides a new dimension in catalyst engineering. This information enables designers to create catalysts with enhanced precision and desired catalytic properties.
- List all other benefits:
Enhanced understanding of interactions between supported ionic liquids and metal nanoparticles, expanding the knowledge base in the field.
Potential for developing more sustainable and efficient catalytic processes, contributing to green chemistry practices.
Insight into modulating electronic properties of catalysts, opening avenues for innovative materials design.
Establishment of a foundation for further research in the design of advanced catalysts and materials for various applications.
Contribution to the broader scientific community by disseminating findings, fostering collaboration and knowledge exchange.
