Liang Linna, Zhong Ye, Chen Jiamin, Zhang Jianguo, Zhang Tonglai, Li Zhimin
State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
China North Advanced Technology Generalization Institute, Beijing 100081, People's Republic of China.
Inorg Chem. 2022 Sep 19;61(37):14864-14870. doi: 10.1021/acs.inorgchem.2c02479. Epub 2022 Sep 8.
A bimetallic MOF, CoNi(EIM)(DCA) (), containing an energetic 1-ethylimidazole (EIM) ligand and a hypergolic linker, dicyandiamide (DCA), was synthesized via a facile method. A fascinating three-dimensional reticular architecture was observed by single-crystal X-ray diffraction in this bimetallic MOF, whereas the corresponding monometallic compounds Co(EIM)(DCA) () and Ni(EIM)(DCA) () were in the mononuclear coordination mode. Uniformly distributed Co and Ni were observed in the bimetallic MOF crystals by SEM-EDS elemental mapping. Bimetallic MOF was thermally stable and insensitive to mechanical stimuli and possessed an excellent energetic density (22.37 kJ·g). Using as a hypergolic promoter, the ignition delay time of 1-butyl-3-methylimidazolium dicyanamide (BMIM DCA) was reduced from 53 to 37 ms, better than that of and as promoters, due to the synergistic catalysis of the bimetal. Furthermore, the thermal decomposition mechanisms of BMIM DCA with , , and were studied by differential scanning calorimetry (DSC). had the best catalytic performance in BMIM DCA thermolysis with a decrease in the decomposition temperature from 314.5 to 308.0 °C and a decrease in the activation energy by 16.3%. All results shed light on the better catalytic effect of the bimetallic MOF on ionic liquid hypergolic ignition than monometallic coordination compounds.
通过简便方法合成了一种双金属金属有机框架材料CoNi(EIM)(DCA)（ ），它含有高能1-乙基咪唑（EIM）配体和自燃连接体二氰胺（DCA）。通过单晶X射线衍射观察到这种双金属金属有机框架呈现出迷人的三维网状结构，而相应的单金属化合物Co(EIM)(DCA)（ ）和Ni(EIM)(DCA)（ ）则处于单核配位模式。通过扫描电子显微镜-能谱仪（SEM-EDS）元素映射在双金属金属有机框架晶体中观察到Co和Ni均匀分布。双金属金属有机框架 热稳定性好，对机械刺激不敏感，具有优异的能量密度（22.37 kJ·g）。以 作为自燃促进剂，1-丁基-3-甲基咪唑二氰胺（BMIM DCA）的点火延迟时间从53毫秒缩短至37毫秒，由于双金属的协同催化作用，其效果优于 和 作为促进剂时的情况。此外，通过差示扫描量热法（DSC）研究了BMIM DCA与 、 和 的热分解机理。 在BMIM DCA热解中具有最佳催化性能，分解温度从314.5℃降至308.0℃，活化能降低了16.3%。所有结果都表明双金属金属有机框架对离子液体自燃点火的催化效果优于单金属配位化合物。
