Layered Boron–Nitrogen–Carbon–Oxygen Materials with Tunable Composition as Lithium‐Ion Battery Anodes

Abstract

The insertion of heteroatoms with different electronegativity into carbon materials can tune their chemical, electronic, and optical properties. However, in traditional solid-state synthesis, it is challenging to control the reactivity of monomers, and therefore, the amount and position of heteroatoms in the final materials. Herein, a simple, scalable, and general molten-state route to synthesize boron-nitrogen-carbon-oxygen (BNCO) materials with tunable boron-nitrogen-carbon composition, as well as electronic and optical properties, is reported. The new synthetic approach consists of polycyclic aromatic hydrocarbons (PAHs) and ammonia-borane as reactants that form a clear liquid-state stage spanning a wide temperature range, before the solid-state reaction. The molten-state stage enhances the control over the synthetic intermediates and final materials, owing to improved monomer miscibility and reactivity. The BNCO composition and optical properties are tuned by the PAH selection and final reaction temperature. The advantages of this method are demonstrated herein through the tunable optical properties, excellent stability to oxidization, facile deposition on substrates, and good activity as an anode material in lithium-ion batteries.

Fluorescent Carbon‐ and Oxygen‐Doped Hexagonal Boron Nitride Powders as Printing Ink for Anticounterfeit Applications

“…Moreover, the broadness of the σ* peak indicates a contribution from the C–N configurations . Similarly, oxygen atoms show doublet π* and σ* peaks at 538 and 546 eV, respectively . Combined, this shows definitively that B, C, N, and O are in an sp 2 ‐hybridized, 2D‐conjugated electron system, rather than a physical mixture …”

“…Here, it is seen that temperature plays a more important role than dwell time with respect to the absorption properties of these materials. The broad absorption around 420 nm are ascribed to carbon‐ and oxygen‐related defects . There is a clear blueshift of these absorption peaks, owing to reduced defects on the surface of the material with increasing temperature.…”

“…For pyrolysis reactions, BCNO is often produced from three precursors, such as boric acid, urea, and polyethylene glycol (PEG) as the B, N, and C sources, respectively . The amount of C is primarily controlled by varying the weight ratio of the carbon source, however it is difficult to precisely control the B:C:N:O ratios due to elemental overlap between O, C, and N in precursors typically used in these syntheses. For example, nitrogen sources such as urea also contain C; O typically exists in two or all of the three commonly used precursor compounds such as boric acid and PEG, making it quite challenging to control the O content in the final BCNO product.…”

Two-dimensional boron nitride as a sulfur fixer for high performance rechargeable aluminum-sulfur batteries

“…demonstrated that graphene supported BN nanosheets displayed an enhanced adsorption of polysulfide over a wide temperature range via the synergetic interaction of BN and graphene 33 . Additionally, these two-dimensional materials can be directly used as electrode materials for batteries 34–38 . Wang et al .…”

Electrochemical Reduction of CO2: Influence of Pre-treating the Carbon Support

“…B-C bond in BC3 structure at 191.3 eV, B-O bond in BCO2 structure at 193.9 eV [18]. It was also detected the presence of borate at 196.5 eV [19]. Regarding the Ketjenblack based samples, the B1s spectrum showed only the presence of the BC3 and BCO2 structures.…”