Facile Template Free Shape Controlled Synthesis of α-Fe2O3 Truncated Octahedral Microstructures for the Thermal Decomposition of Ammonium Perchlorate

Background: The combustion behavior of the solid rocket propellants is highly dependent on the thermal decomposition characteristics of Ammonium Perchlorate (AP) and thus low-cost, facile and scalable preparation of the additive metal oxide-based catalysts is highly desired for the decomposition of AP. Objective: A template free one-step low-cost preparation of α-Fe2O3 for its use as a catalyst in the decomposition of AP. Methods: The catalyst is prepared by the simple heating of ferric chloride at 380 °C without any chemical treatment. The material is characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and high-resolution TEM (HRTEM). The catalytic thermal decomposition of AP over α-Fe2O3 was measured by Differential Scanning Calorimetry (DSC). Results: The material exhibited a pure α-Fe2O3 crystalline phase. Morphological investigations revealed the uniform formation of truncated octahedral microstructures of α-Fe2O3. DSC analysis confirmed the two-step exothermic thermal decomposition of AP with decreased decomposition temperatures with the catalytic assistance of α-Fe2O3. Conclusion: With the catalytic assistance of low-cost and easily prepared α-Fe2O3, the decomposition temperature was decreased by 30 ºC when compared to the pure ammonium perchlorate and a high decomposition heat release of 807 Jg^-1 was observed.