【摘要】 以硝酸铝、葡萄糖为原料,用碳热还原法制备氮化铝粉末,研究尿素对前驱物及其氮化反应产物的组成和显微形貌的影响,发现尿素不仅可以影响前驱物的组成和显微形貌,还对氮化反应产物的显微形貌有重要影响。在溶液里添加尿素后,它与硝酸铝发生了低温燃烧合成反应,生成了比表面积高的泡沫状前驱物,该过程中碳由于燃烧损失较大,在没有添加尿素的溶液中,没有燃烧反应发生,碳的损失小,生成的前驱物团聚现象严重,比表面积低,两种前驱物保留了前驱物的形貌特征,对于不添加尿素合成的前驱物,在其氮化反应后所生成的氮化铝粉末板结严重;而添加尿素合成的前驱物的氮化反应产物是由球形颗粒组成的软团聚体。利用XRD,SEM等分析方法对粉末进行了表征。更多还原

【Abstract】 Aluminum nitride powders were synthesized by carbothermal reduction method from aluminum nitrate and glucose. The effect of urea on the morphology and composition of the precursor and its nitridation products was studied. It is found that urea can affect the morphology and composition of the precursor as well as the morphology of the AIN powders. In the solution added with urea, a low-temperature combustion process takes place between urea and aluminum nitrate and a precursor with high specific surface area is formed, accompanied with lots of carbon lost in this process. While for the solution added with no urea, no combustion reaction takes place and a badly agglomerated precursor is formed. The carbon loss is relatively lower in this process. AIN powders synthesized in our experiment retain the morphology of the precursors. The powders obtained from the precursor prepared withoul urea agglomerate badly, while the powders synthesized from the precursor prepared with urea are soft aggregates of fine particle, which can be easily dispersed. The properties of the powders are determined by means of XRD, SEM, and so on.更多还原