Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (10): 2079-2086.doi: 10.3866/PKU.WHXB201305021

• THERMALANALYSIS KINETICS ANDTHERMOKINETICS • Previous Articles     Next Articles

Effect of Drying Methods on the Structure and Thermal Decomposition Behavior of Ammonium Perchlorate/Graphene Composites

WANG Xue-Bao1, LI Jin-Qing1,2, LUO Yun-Jun1   

  1. 1 School of Material Science & Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China;
    2 cademy of Ordnance Science, Beijing 100089, P. R. China
  • Received:2013-03-04 Revised:2013-05-02 Published:2013-09-26
  • Contact: LUO Yun-Jun E-mail:yjluo@bit.edu.cn
  • Supported by:

    The project was supported by the Basic Research Foundation of Beijing Institute of Technology, China (20110942019).

Abstract:

Graphene hydrogels were prepared by the sol-gel method, and then used to prepare ammonium perchlorate (AP)/graphene composites by the incorporation of AP. The composites were dried naturally in air, freeze-dried, or dried with supercritical CO2. Scanning electron microscopy (SEM), elemental analyses (EA), and X-ray diffraction (XRD) were used to characterize the structure of the AP/graphene composites dried using different methods. Furthermore, the thermal decomposition behavior of the AP/graphene composites was investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis/infrared spectroscopy (TG-FTIR). Drying method had an obvious influence on the morphology of the AP/graphene composites; only the AP/graphene composites dried with supercritical CO2 showed similar three-dimensional networks and porous structure to graphene aerogels. Elemental analyses revealed that the AP contents in the AP/graphene composites prepared by drying naturally, freeze-drying, and supercritical CO2 drying were 89.97%, 92.41%, and 94.40%, respectively. XRD results showed that AP was dispersed homogeneously on the nanoscale in the AP/graphene composites dried with supercritical CO2 and the average particle diameter of AP was about 69 nm. DSC and TG-FTIR analyses indicated that graphene could promote the thermal decomposition of AP, particularly for the sample dried with supercritical CO2. Independent of drying method, the low-temperature decomposition of the as-prepared AP/graphene composites was not observed and the high-temperature decomposition was accelerated. Compared to the other two drying methods, graphene in the AP/graphene composites dried with supercritical CO2 showed most obvious promoting effects. The high-temperature decomposition temperature of the AP/graphene composites dried with supercritical CO2 decreased by 83.7 ℃ compared with that of pure AP, and the total heat release reached 2110 J·g-1. Moreover, graphene also took part in the oxidation reactions with oxidizing products, which was confirmed by the generation of CO2.

Key words: Drying methods, Graphene, Ammonium perchlorate, Sol-gel method, Thermal decomposition

MSC2000: 

  • O643