Graphene functionalization is of great importance in applying graphene as a component in functional devices or in activating it for use as a catalyst. Here we reveal that atomic oxidation of epitaxial graphene grown on a metal substrate results in the formation of enolate, i.e., adsorption of atomic oxygen at the on-top position, on the basal plane of a graphene, using periodic density functional theory calculations. This is striking because the enolate corresponds to the transition state between the epoxides on free-standing graphene and on graphite. Improved interfacial interaction between graphene and the metal substrate during atomic oxidation makes the graphene enolate a local minimum and further highly stabilizes it over the graphene epoxide. Our results provide not only a novel perspective for a chemical route to functionalizing graphene but also a new opportunity to utilize graphene enolate for graphene-based applications.
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http://dx.doi.org/10.1021/ja503664k | DOI Listing |
Org Lett
January 2025
Advanced Research Institute and Department of Pharmaceutical Sciences, Taizhou University, Taizhou, Zhejiang 318000, People's Republic of China.
Herein, we present a metal-free, concise, and efficient protocol for the intermolecular reaction of amides (lactams) with donor-acceptor α-diazo esters to afford the functionalized α-amino-α-aroylethanoates. -Methyl-2-pyrrolidone (NMP) and ,-dimethylformamide (DMF) are employed as both reagents and solvents, allowing for the incorporation of all units into the products. The reaction is processed by the ester group migration and compatible with a broad range of substrates up to 50 examples.
View Article and Find Full Text PDFACS Nano
January 2025
School of Physics and Astronomy, Monash University, Clayton, Victoria 3800, Australia.
Van der Waals electrode integration is a promising strategy to create nearly perfect interfaces between metals and 2D materials, with advantages such as eliminating Fermi-level pinning and reducing contact resistance. However, the lack of a simple, generalizable pick-and-place transfer technology has greatly hampered the wide use of this technique. We demonstrate the pick-and-place transfer of prefabricated electrodes from reusable polished hydrogenated diamond substrates without the use of any sacrificial layers due to the inherent low-energy and dangling-bond-free nature of the hydrogenated diamond surface.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Universitat Bern, Department of Chemistry and Biochemistry, Freiestrasse 3, 3012, Bern, SWITZERLAND.
Isotope Exchange processes are becoming the preferred way to prepare isotopically labelled molecules, avoiding the redesign of multistep synthetic protocols. In the case of deuterium incorporation, the most used strategy has employed transition metals, that offer high reactivity under mild reaction conditions. Despite their success, the trade-off is that these metals are precious, and often exhibit high toxicity.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
University of North Texas, Department of Chemistry, 1508 W Mulberry St, 76201, Denton, UNITED STATES OF AMERICA.
Converting CO2 to high-value fine chemicals represents one of the most promising approaches to combat global warming and subsequently achieve a sustainable carbon cycle. Herein, we contribute an organoboron functionalized ultra-thin metal-organic nanosheet (MON), termed TCPB-Zr-NS, featuring an abundance of exposed Lewis acidic B and formate sites, which can effectively promote CO2 conversion upon the addition of Lewis basic o-phenylenediamines. Compared with the prototypical 3D analogue TCPB-Zr-3D, the resultant TCPB-Zr-NS showcases dramatically improved catalytic activity for the cyclization of o-phenylenediamine as a result of the highly exposed active sites and efficient substrates/products diffusion.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
State Key Laboratory for Chemo/Biosensing and Chemometrics, Advanced Catalytic Engineering Research Center of the Ministry of Education and College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, P. R. China.
The cobalt-nitrogen-carbon (Co─N─C) single-atom catalysts (SACs) are promising alternatives to precious metals for catalyzing the hydrogen evolution reaction (HER) and their activity is highly dependent on the coordination environments of the metal centers. Herein, a NaHCO etching strategy is developed to introduce abundant in-plane pores within the carbon substrates that further enable the construction of low-coordinated and asymmetric Co─N sites with nearby vacancy defects in a Co─N─C catalyst. This catalyst exhibits a high HER activity with an overpotential (η) of merely 78 mV to deliver a current density of 10 mA cm, a Tafel slope of 45.
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