Self-propagating high-temperature synthesis (SHS) or combustion synthesis (CS) is a rapidly developing research area. SHS materials are being used in various fields, including mechanical and chemical engineering, medical and bioscience, aerospace and nuclear industries. The goal of the present paper is to provide a comprehensive state-of-the-art review and to analyse a critical mass of knowledge in the field of SHS materials and coatings. We also briefly discuss the history and scientific foundations of SHS along with an overview of the technological aspects for synthesis of different materials, including powders, ceramics, metal-ceramics, intermetallides, and composite materials. Application of CS in the field of surface engineering is also discussed focusing on two main routes for applying SHS to coating deposition: (i) single-step formation of the desired coatings and (ii) use of SHSderived powders, targets or electrodes in the coating deposition processes.

Smart implementation of novel advanced nanomaterials is the key for the solution of many complex problems of modern science. In recent years, there has been a great interest in the synthesis and application of boron nitride (BN) nanotubes because of their unique physical, chemical, and mechanical properties. By contrast, the synthesis, characterization and exploration of other morphological types of BN nanostructure - BN nanoparticles and BN nanosheets - have received less attention. However, the detailed investigations on advantages of every morphological BN type for specific applications have only recently been started. One of the promising directions is the utilization of BN-based nanohybrids. This review is dedicated to the in-depth analysis of recently published works on the fabrication and application of BN nanoparticles, nanosheets, and their nanohybrids. It covers a variety of developed synthetic methods toward fabrication of such nanostructures, and their specific application potentials in catalysis, drug delivery, tribology and structural materials. Finally, the review focuses on the theoretical aspects of this quickly emerging field.

0 200 -150 0 50 Z (kcm 2 ) Z (kcm 2 )2 Research Highlights  Simple single-step PEO process for production of self-healing coatings on Mg  Benzotriazole loaded halloysite nanotubes incorporated in PEO coatings on Mg  The nanotubes increased mechanical properties of PEO coatings  pH increase at corrosion sites promoted BTA-mediated nucleation of Mg(OH)2  Dense Mg(OH)2 film formed on corrosion sites inhibited pitting corrosion Abstract:Halloysite nanotubes (HNT) and benzotriazole (BTA) loaded HNT were added to a silicatebased electrolyte to produce PEO coatings on AM50 alloy. The coatings were characterised by SEM, EDX and XRD methods. Corrosion behaviour in 3.5 wt.% NaCl was studied by EIS and PDP scans. The HNT increased coating scratch resistance greater than BTA-HNT, although the latter enhanced corrosion resistance due to a self-healing effect. This was triggered by a dense Mg(OH)2 film being formed on corrosion sites following partial coating degradation, preventing pitting corrosion. The single-step process for producing self-healing PEO coatings has good potential in corrosion protection of Mg.

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Nanoparticles (NPs) have a great potential as nanosized drug-delivery carriers. Such systems must safely deliver the drug to the site of the tumor without drug leakage, effectively penetrate inside cancer cells, and provide intracellular drug release. Herein we developed an original and simple method aimed at the fabrication of spherical boron nitride NPs (BNNPs), 100-200 nm in diameter, with peculiar petal-like surfaces via chemical vapor deposition. Such structures were found to be able to absorb a large amount of antitumor drug-killing tumor cells. They revealed low cytotoxicity and rapid cellular uptake. BNNPs were saturated with doxorubicin (DOX) and then dispersed. The BNNPs loaded with DOX (BNNPs-DOX) were stable at neutral pH but effectively released DOX at pH 4.5-5.5. MTT assay and cell growth testing showed that the BNNPs-DOX nanocarriers had been toxic for IAR-6-1 cells. BNNPs loaded with DOX penetrated into the neoplastic IAR-6-1 cells using endocytic pathways, and then DOX released into the cytoplasm and cell nuclei and resulted in cell death.