溶胶玻璃原位合成碳纳米管的研究

In Situ Synthesis of Carbon Nanotubes in Gel Glass

目前,碳纳米管的各种制备方法如电弧法、激光消融法、催化热解法及化学气相沉积法等,都是在500～ 3500℃温度范围内经由气固相接触表面合成的,从而使反应的深度和广度都受到了限制.利用固相热解法尝试在 溶胶玻璃中原位合成碳纳米管,该方法可以使反应在整个固相范围内同时发生,而不只是在气固相的表面合成.在 制备样品的过程中采用了溶胶 凝胶法,成功地将碳源(乙酰丙酮)和催化剂(硝酸钴)均匀地分散在SiO2溶胶玻璃 中,制备了纳米级的复合材料.另外,选择了乙酰丙酮作碳源,将碳纳米管的合成温度降到了400℃,实现了在低温 固相条件下原位合成碳纳米管.最后通过TEM对生成的纳米碳管进行表征.

At present, the synthesis of c ar bon nanotubes (CNTs) is normally conducted on a vapor-to-solid interface at 50 0—3 500 ℃ via various vapor phase methods, such as arc discharge, laser ablation, catalytic pyrolysis, and chemical vapor deposition. T he extent and profundity of reaction is limited. In this paper,we try to synthesize carbon nanotubes by solid-state synthesis in a gel matrix.The reaction can take place simultaneo usly across an entire bulk phase rather than only on intersurface between liquid state.Carbo n nanotubes have been synthesized in a gel matrix prepared by the sol-gel method. Acetylacetone (C 5H 8O 2) was used as a solid-state carbon source and activa tor (Co(NO 3) 2) was preintroduced into a gel matrix. In addition, acetylacetone was chosen to be solid-state carbon source. As a result the synthetical temperature was reduced to 400 ℃, synthesis of carbon nanotubes at low temperature come ture.At last, carbon nanot ubes are described by TEM .