多孔硅/硝酸钆复合材料制备与表征

Preparation and Characterization of Porous Silicon/Gadolinium Nitrate Composite Material

多孔硅/硝酸钆复合材料因具有爆炸能量高和环境危害小等特点而受到世界各国广泛关注。采用电化学阳极氧化法制备新鲜多孔硅并滴加硝酸钆形成复合材料,表征其化学组成与结构。结果表明,当电解液HF与EtOH体积比为1∶1、电流密度为50mA.cm-2、阳极氧化时间为30min时,形成的多孔硅孔隙率较大,适宜与硝酸钆形成复合材料;与新鲜多孔硅相比,滴加硝酸钆乙醇溶液的多孔硅在1675、1534、1382和1217cm-1出现了4个新的吸收峰,结合N1s和Si2p结合能有明显化学位移的现象,表明硝酸钆乙醇溶液与多孔硅之间存在相互作用,结构中有—NH2形成,表面Si—Hx键被氧化为Si—O键;当电火花触发时,观察到多孔硅/硝酸钆复合材料爆炸现象。

Porous silicon/gadolinium nitrate composite material is widely focused on its high explosion energy and low environmental hazard. The composite material was formed by dropping ethanol solution of gadolinium nitrate to the surface of the fresh porous silicon prepared by electrochemical anodization; both chemical composition and structure of the composite were characterized as well. Results showed that the fresh porous silicon prepared under the conditions of the volume ratio of HF/EtOH = 1 ： 1, current density 50mA/cm2 and anodizing time 30 min has a larger porosity and is more suitable to form composite with gadolinium nitrate. Compared with fresh porous silicon, four new absorption peaks appeared at 1675, 1534, 1382 and 1217cm-1 , and there was an obvious chemical shift of binding energy of N16s and Si2p for as-prepared composite material. Those mean the -NH2 bond had been formed and Si-Hx bond had been oxidized to Si--O bond,that is, there were the interaction between gadolinium nitrate ethanol solution and porous silicon. When triggered by electric spark, porous silicon/gadolinium nitrate composite material exhibited explosion characteristics.