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Atomically thin boron nitride (BN) nanosheets were generally considered to be chemically inert until the recent discovery of the surprising catalysis. However, the origin of this unusual catalytic activity remains unclear. We have observed the free boron radicals at the edges and defective sites of BN nanosheets and demonstrated with both experimental and theoretical approaches that the boron radicals in the nanosheets can catalyze the chromogenic reaction of 3,5,3′,5′-tetramethylbenzidine and serve as a source of reactive radicals for the co-reactant electrogenerated chemiluminescence of tris(2,2′-bipyridine)ruthenium(2+). These findings suggest BN nanosheets as a type of nonmetal catalyst.

The properties and applications of boron nitride (BN) nanosheets are complementary to those of graphene, with advantages in chemical and thermal stability. Biocompatibility is an important property for future biomedical applications but has not been investigated experimentally. We studied the biocompatibility of BN nanosheets of different sizes and compared it with that of BN nanoparticles in osteoblast-like cells (SaOS2). Our results showed that the biocompatibility of BN nanomaterials depends on their size, shape, structure, and surface chemical properties. Electron spin resonance measurement revealed that unsaturated B atoms located at the nanosheet edges or on the particle surface are responsible for the cell death.

This study charted that the functionalized boron nitride with different functional groups can improve the performance of the Lithium-Sulfur batteries with different ways and can be used as the interlayers and the separators. It also proved a possibility of the application of liquid cathode system in Lithium-Sulfur batteries.

The development of advanced thermal transport materials is a global challenge. Two-dimensional nanomaterials have been demonstrated as promising candidates for thermal management applications. Here, we report a boron nitride (BN) nanosheet/polymer composite film with excellent flexibility and toughness prepared by vacuum-assisted filtration. The mechanical performance of the composite film is highly flexible and robust. It is noteworthy that the film exhibits highly anisotropic properties, with superior in-plane thermal conductivity of around 200 W m−1 K−1 and extremely low through-plane thermal conductivity of 1.0 W m−1 K−1,making this material an excellent candidate for thermal management in electronics. Importantly, the composite film shows fire-resistant properties. The newly developed unconventional flexible, tough, and refractory BN films are also promising for heat dissipation in a variety of applications

Two-dimensional (2D) materials can be produced using ball milling with the help of liquid surfactants or solid exfoliation agents, as ball milling of bulk precursor materials usually produces nanosized particles because of high-energy impacts. Post-milling treatment is thus needed to purify the nanosheets. We show here that nanosheets of graphene, BN, and MoS2 can be produced by ball milling of their bulk crystals in the presence of ammonia or a hydrocarbon ethylene gas and the obtained nanosheets remain flat and maintain their single-crystalline structure with low defects density even after a long period of time; post-milling treatment is not needed. This study does not just demonstrate production of nanosheets using ball milling, but reveals surprising indestructible behaviour of 2D nanomaterials in ammonia or hydrocarbon gas under the high-energy impacts; in other milling atmospheres such as air, nitrogen or argon the same milling treatment produces nanosized particles. A systematic study reveals chemisorption of ammonia and hydrocarbon gases and chemical reactions occurring at defect sites, which heal the defects by saturating the dangling bonds. Density functional theory was used to understand the mechanism of mechanochemical reactions. Ball milling in ammonia or hydrocarbon is promising for mass-production of pure nanosheets.

Pure graphene is known as the strongest material ever discovered. However, the unavoidable defect formation in the fabrication process renders the strength of defective graphene much lower (~14%) than that of its perfect counterpart. By means of density functional theory computations, we systematically explored the effect of gas molecules (H2, N2, NH3, CO, CO2 and O2) adsorption on the mechanical strength of perfect/defective graphene. The NH3 molecule is found to play a dominant role in enhancing the strength of defective graphene by up to ~15.6%, while other gas molecules decrease the strength of graphene with varying degrees. The remarkable strength enhancement can be interpreted by the decomposition of NH3, which saturates the dangling bond and leads to charge redistribution at the defect site. The present work provides basic information for the mechanical failure of gas-adsorbed graphene and guidance for manufacturing graphene-based electromechanical devices.