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Boron nitride (BN) is one of III–V compounds widely applied on the electrical industry. It has been fabricated by numerous techniques, but so far there is no reliable method to produce pure and high-yielding BN nanotubes at relatively lower temperature. Therefore, the exploration on its synthesis is still a challenging subject. In the study, the BN nanotube would be synthesized by thermal-heating chemical vapor deposition (TH-CVD) with trimethyl borate evaporated at 60 °C and nitrogen gas flew into reaction chamber as the source of B and N, respectively. 434 stainless steel wires will be coiled as an entangled wire scaffold with pore size of 1 mm and then placed in the middle part of reaction chamber. The metallic ions contained in the stainless steel will serve as the catalysts for of BN nanotube in situ growth. From the results of SEM, HRTEM, FTIR and XRD analysis, hexagonal-BN (h-BN) and orthorhombic-BN (o-BN) nanotubes were successfully synthesized at relatively low temperature between 1000 and 1200 °C. All the nanotubes prepared in the system were identified as h-BN and o-BN. At reaction temperature of 1200 °C, several types of BN morphology appeared. The BN nanotubes could be obtained at the temperature between 1000 and 1100 °C. However, BN nanotubes for the latter temperature grow into larger size tube. The optimum reaction temperature for BN nanotube synthesis is 1000 °C. The reproduction property of synthesized BN nanotube by this method is very promising. The method should have a great potential to prepare BN nanotube in the future.

In the study, we are going to develop a tri-layer membrane as the artificial skin for extensive burn injury. The first layer is a three-dimensional tri-copolymer sponge of gelatin/hyaluronan/chodroitin-6-sulfate with 70% in porosity and 20–100 μm in pore size. The layer is constructed as a dermis analogous layer to stimulate capillaries penetration, to promote dermal fibroblast migration and to induce the secretion of extra-cellular matrix, which provides a better physiological environment for burn patient recovery. The second layer is as so called auto-stripped layer composed by poly-N-isopropyacrylamide (PNIPAAm). The layer will be automatically peeled off from the tri-copolymer layer once the wound site closed and recovered. The third layer is composed by polypropylene (PP) non-woven fabric, which provides an open structure for exudates drainage out that will reduce the risk of second infection. The tri-layer wound dressing has been successfully prepared by subsequently high-energy plasma treatment, γ-ray irradiation, UV light exposure, and lyophilized process. From the results of MTT, IL-8, IL-1α, IL-6, and TNF-α measurement, the developed material will not induce tissue inflammatory or immune response. The dermal fibroblasts showed initial contact with the material surface through the radial extension of filopodia followed by cytoplasmic webbing that could be examined by SEM. Dermal fibroblasts subsequently flattened for further proliferation and extra-cellular matrix secretion. Dermal analog layer provides a three-dimensional architecture for normal dermis regeneration. The layer can be completely biodegraded within 4 weeks post-operation. After served as a scaffold for the ingrowth of self-fibroblasts, a normal dermis like layer will be regenerated. The dressing will fall off automatically without any damage once the wound site healed completely.

Thermal-heating chemical-vapor deposition has been used to synthesize Si3N4 nanotubes by heating tetra-ethyl-ortho-silicate at 165 °C to get vapor to flow in and providing nitrogen gas to the reaction chamber as the source of Si and N, respectively. A stainless-steel wire was coiled as entangled wire scaffold with a pore size of 1 mm. The wire scaffold was placed in the middle part of the reaction chamber. Cr, Fe and Mo, contained in the stainless-steel, served as catalysts to provide in situ growth of Si3N4 nanotubes on the coil surface at a relative low reactant temperature (1000 °C) through the vapor–liquid–solid growth mechanism. Most of the nanotubes are end-closed by a metallic particle. All the nanotubes were identified as α-Si3N4 in crystal structure.