物理化学学报

所属专题: 热分析动力学和热动力学

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两种形貌纳米Fe2O3对TKX-50热分解的催化性能研究

张明, 赵凤起, 杨燕京, 李辉, 张建侃, 马文喆, 高红旭, 李娜   

  1. 西安近代化学研究所, 燃烧与爆炸技术重点实验室, 西安 710065
  • 收稿日期:2019-04-06 修回日期:2019-04-22 录用日期:2019-04-22 发布日期:2019-04-24
  • 通讯作者: 赵凤起 E-mail:zhaofqi@163.com
  • 基金资助:
    国家自然科学基金(21173163,21503163)资助项目

Shape-Dependent Catalytic Activity of Nano-Fe2O3 on the Thermal Decomposition of TKX-50

ZHANG Ming, ZHAO Fengqi, YANG Yanjing, LI Hui, ZHANG Jiankan, MA Wenzhe, GAO Hongxu, LI Na   

  1. Science and Technology on Combustion and Explosion Laboratory, Xi'an Modern Chemistry Research Institute, Xi'an 710065, P. R. China
  • Received:2019-04-06 Revised:2019-04-22 Accepted:2019-04-22 Published:2019-04-24
  • Contact: ZHAO Fengqi E-mail:zhaofqi@163.com
  • Supported by:
    The project was supported by the National Natural Science Foundation of China (21173163, 21503163).

摘要: 作为固体推进剂的重要组分,单质炸药有助于提升固体推进剂能量特性,且其热分解性能显著影响推进剂的燃烧特性。1,1'-二羟基-5,5'-联四唑二羟胺盐(TKX-50)兼具高能和低感度(摩擦和冲击感度)的特性,在固体推进剂领域中具有较好的应用前景。纳米催化剂的添加可显著调节单质含能材料的热分解性能,进而影响推进剂的燃烧性能。而目前纳米级催化剂较少被用于TKX-50热分解的研究中,且未涉及催化剂形貌影响TKX-50热分解性能的相关研究。基于Fe2O3对TKX-50热分解较好的催化性能,通过溶剂热法合成了两种形貌(球形和管状)的纳米Fe2O3颗粒,并通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)和X射线光电子能谱(XPS)等对其形貌、组成和结构进行表征。XRD、FTIR和XPS证实了Fe2O3的成功制备,SEM和TEM图显示球形Fe2O3样品由110 nm的Fe2O3颗粒团聚而成;管状Fe2O3表现出中空结构,平均直径为120 nm,长为200 nm。采用热重分析(TG)和差示扫描量热分析(DSC)研究了管状和球形Fe2O3对TKX-50热分解的催化性能,并通过等转化率法计算了热分解活化能。结果表明,两种形貌的Fe2O3均可有效促进TKX-50热分解,而管状Fe2O3的催化效果更佳,可显著降低TKX-50的分解峰温和活化能。管状Fe2O3更好的催化性能来自于其中空结构可提供更多的催化活性位点,有助于TKX-50的热分解。

关键词: Fe2O3, 热分解, TKX-50, 形貌, 催化

Abstract: Energy components used in solid rocket propellants are beneficial for improving the energy performance, and their thermal decomposition characteristics significantly affect the combustion properties of the propellants. As a kind of energetic material with both high energy and low sensitivity (impact and friction), 5,5'-bistetrazole-1,1'-diolate (TKX-50) can effectively improve the energy and safety characteristics of solid propellants. Burning catalyst is another important component of solid propellants, which can significantly improve the burning rate of the propellant and reduce the pressure exponent. Among various burning catalysts, nanoscale transition metal oxides can promote the thermal decomposition of the energetic component, thus enhancing the combustion properties of the solid propellant. However, the catalytic effects of nanoscale transition metal oxides with different morphologies on the thermal decomposition of TKX-50 have rarely been studied. Based on the excellent catalytic activity of Fe2O3 for TKX-50 thermal decomposition, nano-Fe2O3 particles with spherical and tubular microstructures were used for TKX-50 thermal decomposition. The Fe2O3 nanoparticles were successfully fabricated via the solvothermal method and characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) analyses. The XRD, FT-IR, and XPS results confirmed the successful fabrication of spherical and tubular Fe2O3 samples. The SEM and TEM images showed that the spherical Fe2O3 samples are composed of agglomerated Fe2O3 nanoparticles with an average particle size of 110 nm. In addition, the average diameter and length of hollow tubular Fe2O3 nanoparticles are 120 nm and 200 nm, respectively. The catalytic activities of spherical and tubular Fe2O3 for TKX-50 decomposition were studied by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) methods. The DSC and TG-DTG curves showed that both tubular and spherical Fe2O3 could effectively promote TKX-50 thermal decomposition. The first thermal decomposition peak temperature (TFDP) of TKX-50 was reduced by 36.5 K and 26.3 K in the presence of tubular and spherical Fe2O3, respectively, at 10 K·min-1. The activation energy (Ea) of TKX-50, determined by the iso-conversional method, was significantly reduced in the presence of both tubular and spherical Fe2O3. The results indicated that the microstructure of the catalyst has a significant effect on its catalytic performance for TKX-50 thermal decomposition, and that tubular Fe2O3 with hollow microstructure possesses better catalytic activity than spherical Fe2O3. The excellent catalytic activity of tubular Fe2O3 can be attributed to the hollow microstructure, which has more active sites for TKX-50 thermal decomposition.

Key words: Fe2O3, Thermal decomposition, TKX-50, morphology, Catalysis

MSC2000: 

  • O642