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In this paper, the interlayer sliding between graphene and boron nitride (h-BN) is studied by molecular dynamics simulations. The interlayer shear force between h-BN/h-BN is found to be six times higher than that of graphene/graphene, while the interlayer shear between graphene/h-BN is approximate to that of graphene/graphene. The graphene/h-BN heterostructure shows several anomalous interlayer shear characteristics compared to its bilayer counterparts. For graphene/graphene and h-BN/h-BN, interlayer shears only exit along the sliding direction while interlayer shear for graphene/h-BN is observed along both the translocation and perpendicular directions. Our results provide significant insight into the interlayer shear characteristics of 2D nanomaterials.

In this paper, a novel low dimensional boron nitride nanoribbons (BNNRs) aerogels were successfully developed by a cost-effective, catalyst-free chemical vapor deposition using Boric acid and Melamine as the B and N sources. The obtained BNNRs aerogels were possessed porous structure (average pore diameter: 2 nm) and the width of a single nanoribbon was approximately 200 nm and large aspect ratio more than 50 times and the BET surface area of 530 m2/g approximately. Attractively, BNNRs aerogels exhibited an excellent adsorption capacity for both PEDOT: PSS (3, 4-ethylenedioxyethiophene: polystyrene sulfonate) (6020 mg/g) and mustard seed oil (5010 mg/g). The adsorbed BNNRs aerogels can be cleaned and reused by burning them in the air and they create favorable conditions for recycling. After comparison, our experimental study found that after two test cycles, the adsorption ratio of BNNRs aerogels to mustard seed oil was 261.28%, which was only 6.97% less than that of the first adsorption with 280.87%. After the 4 combustion-adsorption cycles, the aerogels also maintained a 105.53% adsorption ratio, which confirmed the ability of BNNRs aerogels to adsorb oil. Therefore, BNNRs aerogels material is a promising nanomaterial for environmental remediation and selective water purification and treatment.

The paper presents a numerical study of defect-free single-wall carbon, boron nitride and silicon carbide armchair and zigzag nanotubes, through a simple stick-and-spring model, based on Morse and cosine potential functions. The study investigates the relaxed configuration of the tubes and gives a comprehensive evaluation of their elastic constants, which is performed by framing tensile, torsional and radial tests within the membrane behaviour of a Donnell thin shell model. Extensive comparisons with reference ab-initio results are given and used to refine some parameters of the potential functions for hexagonal silicon carbide nanomaterials.

Based on their unique material properties, two-dimensional (2D) nanomaterials such as graphene, molybdenum disulfide (MoS2), and boron nitride (BN) have been attracting increased research interest. The potential of 2D materials, in the form of nanoplatelets that are used as new materials, will be important to both nanomaterials and advanced materials. Water is usually considered to be the ideal dispersed medium, and the essential hydrophobicity and limitations to mass production of 2D nanoplatelets have become quite serious obstacles to their usage in various fields. In this paper, pulping black liquor was used as dispersant, with high concentration of lignin to get single- and few-layered nanoplatelets. The whole process required only the high-shear mixing of 2D layered materials and pulping waste liquor. This method was not only simple and efficient but also environmentally friendly and resource-recycling. Moreover, the fabricated single- or few-layered nanoplatelets possessed good solubility in aqueous solution due to their edge functionalization, and could be well dispersed in water at concentrations (10 mg ml-1 for graphene, 6.3 mg ml-1 for MoS2, and 6.0 mg ml-1 for BN) which were much higher than that of other methods. The dispersions of graphene, MoS2, and BN nanosheets were highly stable over several months, which allowed us to easily prepare graphene, MoS2, and BN films through simple vacuum filtration or spraying. These results indicated that pulping black liquor can be used as a material or reagent, and the mass production of 2D material is possible in a simple and fast method.

In this paper, we describe the effects of the combination of topographical, mechanical, chemical and intracellular electrical stimuli on a co-culture of fibroblasts and skeletal muscle cells. The co-culture was anisotropically grown onto an engineered micro-grooved (10 µm-wide grooves) polyacrylamide substrate, showing a precisely tuned Young's modulus (∼ 14 kPa) and a small thickness (∼ 12 µm). We enhanced the co-culture properties through intracellular stimulation produced by piezoelectric nanostructures (i.e., boron nitride nanotubes) activated by ultrasounds, thus exploiting the ability of boron nitride nanotubes to convert outer mechanical waves (such as ultrasounds) in intracellular electrical stimuli, by exploiting the direct piezoelectric effect. We demonstrated that nanotubes were internalized by muscle cells and localized in both early and late endosomes, while they were not internalized by the underneath fibroblast layer. Muscle cell differentiation benefited from the synergic combination of topographical, mechanical, chemical and nanoparticle-based stimuli, showing good myotube development and alignment towards a preferential direction, as well as high expression of genes encoding key proteins for muscle contraction (i.e., actin and myosin). We also clarified the possible role of fibroblasts in this process, highlighting their response to the above mentioned physical stimuli in terms of gene expression and cytokine production. Finally, calcium imaging-based experiments demonstrated a higher functionality of the stimulated co-cultures.

This paper reports on two examples of biomedical applications of ceramic nanoparticles. Thanks to their physical and chemical inertia, barium titanate nanoparticles and boron nitride nanotubes have been proved to have an optimal in vitro biocompatibility, even at high concentrations. Barium titanate nanoparticles-doxorubicin composites are successfully internalized by cancer cells, and allow for a considerable enhancement of drug up-take. Conversely, boron nitride nanotubes are explored as “nanotransducers”, thanks to their excellent piezoelectric properties. These two examples encourage further investigations and applications in biology and medicine of ceramic nanomaterials, that exhibit interesting advantages respect to traditional materials.