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Introduction of Protonated Sites on Exfoliated, Large-Area Sheets of Hexagonal Boron Nitride.

A new interesting article has been published in ACS Nano. 2018 Oct 23;12(10):9931-9939. doi: 10.1021/acsnano.8b03651. Epub 2018 Sep 25. and titled:

Introduction of Protonated Sites on Exfoliated, Large-Area Sheets of Hexagonal Boron Nitride.

Authors of this article are:

Jasuja K, Ayinde K, Wilson CL, Behura SK, Ikenbbery MA, Moore D, Hohn K, Berry V.

A summary of the article is shown below:

Hexagonal boron nitride (h-BN) sheets possess an exclusive set of properties, including wide energy band gap, high optical transparency, high dielectric breakdown strength, high thermal conductivity, UV cathodoluminescence, and pronounced thermochemical stability. However, functionalization of large h-BN layers has remained a challenge due to their chemical resistance and unavailable molecular-binding sites. Here we report on the protonation of h-BN via treatment with chlorosulfonic acid that not only exfoliates “large” h-BNs (up to 10 000 μm2) at high yields (∼23%) but also results in their covalent functionalization by introducing four forms of aminated nitrogen (N) sites within the h-BN lattice: sp2-delocalized and sp3-quaternary protonation on internal N sites (>N+═ and >NH+-) and pyridinic-like protonation on the edge N sites (═NH+- and -NH-). The presence of these groups transforms the chemically passive h-BN sheets to their chemically active form, which as demonstrated here can be used as scaffolds for forming composites with plasmonic gold nanoparticles and organic dye molecules. The dispersion of h-BNs exhibits an optical energy band gap of 5.74 eV and a zeta potential of ζ = +36.25 mV at pH = 6.1 (ζmax = +150 mV), confirming high dispersion stability. We envision that these two-dimensional nanomaterials with an atomically packed honeycomb lattice and high-energy band gap will evolve next-generation applications in controlled-UV emission, atomic-tunneling-barrier devices, ultrathin controlled-permeability membranes, and thermochemically resistive transparent coatings.

Check out the article’s website on Pubmed for more information:

This article is a good source of information and a good way to become familiar with topics such as:

Raman;exfoliation;functionalization;hexagonal boron nitride;protonation


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