Synthesis of fine boron nitride powders by combining direct boron nitridation with carbothermic boron oxide reduction

Thermal properties and formation mechanism of h‐BN nanoneedles synthesized via carbothermic reduction reaction

“…Thus, the weight gain was about 30% and 60% for the two samples, which respectively correspond to the oxidized amount being approximately 12% and 24%. The weights gain of the two composite samples was resulting from a very small percent of oxidized boron carbide with the formation of a protective B 2 O 3 layer according to the following chemical reaction 7: B 4 C ðsÞ þ 4O 2ðgÞ ¼ 2B 2 O 3ðlÞ þ CO 2ðgÞ (7) As noticed, LB3N sample has got a higher weight gain than LB1N sample, as indicated by the TG curve. The small particle size with a high surface area initiates the oxidation reaction, and so much amount of boron carbide oxidized.…”

“…H‐BN, as an excellent ceramic material, has beneficial properties such as high melting point, low density, high chemical inertness, high thermal conductivity, low friction coefficient, transparency, and high electrical resistivity . H‐BN has a graphite‐like layered structure called white graphite, which grant the lubricious and softening nature of BN . These advantages promote h‐BN to be utilized in many advanced applications such as lubricants, refractories, electrical insulators, ceramic composites, laser devices, and catalyst supports …”

“…5 H-BN has a graphite-like layered structure called white graphite, which grant the lubricious and softening nature of BN. 6,7 These advantages promote h-BN to be utilized in many advanced applications such as lubricants, refractories, electrical insulators, ceramic composites, laser devices, and catalyst supports. 8 Boron nitride ceramic composites are very probable to promote BN for modern applications.…”

Large‐scale synthesis of hexagonal boron nitride nanosheets and their improvement in thermal properties of epoxy composites

“…The epoxy nanocomposites were prepared as follows: first, the desired amount of BNNSs or ATBNNSs [1,3,5,7,9,15, and 25 wt%, here, the wt% 5 fillers (weight)/ epoxy matrix (weight)] was added to a 250 ml beaker containing 16 g epoxy resin, respectively, stirred in water bath at 80 C for 2 h. The homogeneous solution was then cooled down to ambient temperature; Second, 8 g amine curing agent was added to the preobtained homogeneous solution step-by-step under constant stirring; Afterward, the temperature was increased to 60 C and the mixed solution was intensively agitated for 30 min, followed by removing gases in the solution for 10 min; Finally, the mixture was poured into a plastic mold, and cured for at least 48 h at ambient temperature for further measurements.…”

“…Boron nitride (BN), a structural analog of carbon, exists in layered [hexagonal BN (h‐BN)], spherical, cubic, and tubular structures similar to graphite, fullerene, diamond, and CNT phases . Among these polymorphs, h‐BN is the most stable and soft structure, often referred to as “white graphite” . However, unlike graphite, h‐BN has many unique advantages such as prominent electrical insulativity, excellent thermal conductivity, and superb chemical/thermal stability .…”