$$\textit{Ex}\,\textit{situ}$$ Ex situ synthesis of G/ $$\upalpha $$ α - $$\hbox {Fe}_{2}\hbox {O}_{3}$$ Fe 2 O 3 nanocomposite and its catalytic effect on the thermal decomposition of ammonium perchlorate

Abstract

$$\upalpha $$ - $$\hbox {Fe}_{2}\hbox {O}_{3}$$ nanoparticles were prepared by a facile hydrothermal method using ferric chloride hexahydrate ( $$\hbox {FeCl}_{3}{\cdot }$$ 6H $$_{2}\hbox {O}$$ ) as a precursor. Graphene oxide (GO) was synthesized using a modified Hummers method and graphene nanosheets (G) were successfully obtained by thermal reduction of GO. G/ $$\upalpha $$ - $$\hbox {Fe}_{2}\hbox {O}_{3}$$ nanocomposite was prepared using ex situ synthesis in the presence of $$\upalpha $$ - $$\hbox {Fe}_{2}\hbox {O}_{3}$$ nanoparticles and GO solution. The characterization of the as-prepared materials was performed using X-ray diffraction analyses and Fourier transform infrared spectroscopy; their morphology was investigated by scanning electron microscopy and transmission electron microscopy; the specific surface area ( $$S_{\mathrm{BET}}$$ ) was determined by nitrogen adsorption; their catalytic activity on the thermal decomposition of ammonium perchlorate (AP) was investigated by differential thermal analysis (DTA). The results of DTA indicated that the obtained nanomaterials contribute in ameliorating the thermal decomposition of AP; specifically, the high decomposition temperature of AP decreases from 432 to 380 $$^{\circ }$$ C. A significant decrease in the activation energy was also achieved in the presence of these nanomaterials, and the mixture of ammonium perchlorate with G/ $$\upalpha $$ - $$\hbox {Fe}_{2}\hbox {O}_{3}$$ showed the lowest value (from 129 to $$80.33\,\hbox {kJ}\,\hbox {mol}^{-1}$$ ). Graphene (G), $$\upalpha $$ - $$\hbox {Fe}_{2}\hbox {O}_{3}$$ nanoparticles and G/ $$\upalpha $$ - $$\hbox {Fe}_{2}\hbox {O}_{3}$$ nanocomposite are successfully obtained using a simple hydrothermal method. The results of DTA show that the G/ $$\upalpha $$ - $$\hbox {Fe}_{2}\hbox {O}_{3}$$ nanocomposite displays the best catalytic activity in enhancing the thermal decomposition of ammonium perchlorate by reducing its HTD from 432 $$^{\circ }$$ C to 380 $$^{\circ }$$ C.