Revealing the correlation between adsorption energy and activation energy to predict the catalytic activity of metal oxides for HMX using DFT

Traditional selection of combustion catalysis is time-consuming and labor-intensive.Theoretical calculation is expected to resolve this problem.The adsorption energy of HMX and O atoms on 13 metal oxides was calculated using DMol3,since HMX and O are key substances in decomposition process.And the relationship between the adsorption energy of HMX,O on metal oxides(TiO_(2),Al_(2)O_(3),PbO,CuO,Fe_(2)O_(3),Co_(3)O_(4),Bi_(2)O_(3),NiO)and experimental T30 values(time required for the decomposition depth of HMX to reach 30%)was depicted as volcano plot.Thus,the T30 values of other metal oxides was predicted based on their adsorption energy on volcano plot and validated by previous experimental data.Further,the adsorption energy of HMX on ZrO_(2)and MnO_(2)was predicted based on the linear relationship between surface energy and adsorption energy,and T30 values were estimated based on volcano plot.The apparent activation energy data of HMX/MgO,HMX/SnO_(2),HMX/ZrO_(2),and HMX/MnO_(2)obtained from DSC experiments are basically consistent with our predicted T30 values,indicating that it is feasible to predict the catalytic activity based on the adsorption calculation,and it is expected that these simple structural properties can predict adsorption energy to reduce the large quantities of computation and experiment cost.

三维氧化铁/石墨烯的构建及其对CL-20的热分解性能的影响

首先采用水热法合成了两种不同形貌的氧化铁(棒状rFe2O3和颗粒状pFe2O3),然后采用界面自组装法制备了两种具备高比表面积和三维网状结构的氧化铁与石墨烯的复合物(rFe2O3/G和pFe2O3/G)。通过X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电镜(TEM)和X射线光电子能谱(XPS)对样品的相态、组成及结构性质进行确证。根据热重-红外联用分析(TGA-IR)和差式扫描量热法(DSC)测试对所制备的催化剂对CL-20的催化热分解活性进行评估。通过逻辑选择法对Cl-20、Fe2O3/Cl-20和Fe2O3/G/CL-20的非等温热分解动力学进行系统研究发现,其均遵循相同的机理函数模型。对比分析表明,棒状氧化铁/石墨烯复合物(rFe2O3/G)对CL-20的热分解表现出最佳的催化活性。以rFe2O3及rFe2O3/G为样本,研究其对CL-20撞击感度的影响。测试结果表明,rFe2O3/G比rFe2O3更能有效降低Cl-20的撞击感度。综合分析可知,rFe2O3与石墨烯的结合不仅能够促进Cl-20的热分解,且能同时提高Cl-20的安全性能。