模板法制备多孔核/壳结构的Fe2O3/Al纳米铝热薄膜

通过聚苯乙烯(PS)胶晶球模板法制备出三维有序大孔(3DOM)α-Fe₂O₃薄膜骨架, 再利用磁控溅射将Al沉积到3DOM α-Fe₂O₃骨架上得到核/壳结构的Fe₂O₃/Al纳米铝热复合薄膜。扫描电镜(SEM)测试结果表明: 纳米Al均匀地附着在α-Fe₂O₃骨架表面, 骨架孔结构由原先的近圆形转变为Al沉积后的类菱形, 孔壁的厚度从32 nm增加到100 nm; 采用X射线能谱(EDS)对Fe₂O₃/Al纳米铝热薄膜的元素含量进行了分析; 由差示扫描量热法(DSC)分析显示铝热薄膜在490℃开始反应, 经历固-固和固-液两个反应阶段, 总放热量达到1374.7 J/g; 使用激光点火器对铝热薄膜进行点火, 薄膜飞溅出火花并伴有明亮刺眼的亮光, 整个发火时间达2.6 ms, 显示其能被点火并发生自蔓延反应, 可作为一种理想的点火材料。

Preparation of Porous Core/Shell Structure Fe2O3/Al Nanothermite Membrane by Template Method

A three-dimensionally ordered macroporous(3DOM) α-Fe₂O₃ membrane was prepared by inversing polystyrene(PS) spheres colloidal crystal template, and nano aluminum was then introduced into the 3DOM α-Fe₂O₃ skeleton using magnetron sputtering method. Scanning electron microscope(SEM) images show that nano Al coats on surface of α-Fe₂O₃ skeleton uniformly, and pore structure converts into a kind of diamond from previously suborbicular after aluminizing with wall thickness increasing from 32 nm to 100 nm. Simultaneously, elemental analysis of the membrane is investigated via energy dispersive spectrum(EDS). Differential scanning calorimety(DSC) results indicate that onset temperature of the Fe₂O₃/Al nanothermite membrane is 490℃, and thermite reaction between Al and Fe₂O₃ can be divided into solid-solid reaction and liquid-solid reaction. The total heat release is 1374.7 J/g. Ignition performance of the energetic membrane is investigated by laser ignition test. Sparks spatter outward with dazzling light can be observed for 2.6 ms, demonstrating that Fe₂O₃/Al nanothermite membrane can be ignited normally.