泡沫碳化硅陶瓷表面纳米多孔碳化硅涂层的制备

Preparation of nanoporous SiC coating on SiC foam

利用硅改性树脂中硅元素和碳元素分子级均匀分散的特征,以硅改性树脂为涂层原料,在泡沫碳化硅陶瓷表面原位生成了多孔碳化硅活性涂层。在加入适量活性炭颗粒的条件下,在泡沫碳化硅陶瓷表面得到了性能良好的纳米碳化硅涂层,适合作为催化剂载体。相反,在没有活性炭颗粒加入的情况下,所得涂层龟裂、结合强度低,且碳化硅团聚成片,比表面积小。

Nanoporous silicon carbide （SIC） coating was successfully fabricated on foam-shaped SiC ceramics by using silicon-modified phenolic resin as the coating material. The molecular level mixed silicon and carbon elements in the coating material led to in situ formation of nanoscale SiC particles and pores during the subsequent carbothermal reduction reaction. Adding an appropriate amount of activated carbon into the modified resin was beneficial for fabrication of high quality nanoporous SiC coating on foam SiC suitable for catalyst support use. By contrast, without adding activated carbon, deflects such as weak adhesion, particle aggregation and cracks were observed in the coating. Meanwhile, the specific surface area of the fabricated composite was low.