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View Video Presentation: https://doi.org/10.2514/6.2021-3337.vid The pyrotechnic and thermite mixtures of fuels and oxidizers that store high amounts of energy are activated by a specific well defined electrical impulse. These compositions find many applications particularly in micro-chip initiators, microelectromechanical systems (MEMS)-based microthruster systems for microspacecrafts and can also be used as triggering materials for the inflation of automobile airbags. Aluminum (Al) and nano-sized boron (B) are attractive fuel types with their high heat of combustion and high energy density. In the scope of this study, in order to compare the effects of fuel on the performance of nanocomposites; magnesium (Mg) and magnesium coated boron (20%Mg-B) were used addition to Boron. Here, iron oxide is used as an oxidizer and synthesized via sol-gel method by using a broad range of proton scavengers as propylene oxide, tetrahydrofuran, tetrahydropyran, 1,4 dioxane and ammonium hydroxide to investigate the effects of proton scavenger and drying conditions on the structural properties of the synthesized iron oxide xerogels. Fuel rich thermite compositions were prepared by mixing nanostructured Fe2O3 xerogel with metal powders in order to test the combustion performance of metal-iron oxide nano-composites. The effects of the proton scavenger and the fuel on the performance and energetic properties of the nano-composites were evaluated according to their combustion characteristics. It was observed that the iron oxide xerogel samples presented nano-sized structures. Even the samples synthesized with propylene oxide showed the smallest heat output, the average calorific value was tailored from 2464 J/g to 5540 J/g by using Mg instead of B as a fuel. It was further identified that the heat output of the compositions prepared with propylene oxide was enhanced with 20%Mg coated B. Mg that coats the B particle enhances the combustion with its easily ignitable characteristics and as well as keep the surface of B clear of oxide layer as possible. The average calorific values of Mg/Fe2O3 with 1,4 dioxane and ammonium hydroxide reach to 6858 J/g and 7740 J/g which are the highest values among the samples. Boron still is a good candidate for the compositions containing Fe2O3 synthesized with THF. The results suggest that the type of proton scavenger used in synthesis of iron oxide has triggered a different type of reaction mechanisms during the combustion of fuel with oxidizer. Herein, it was identified that both the proton scavenger and the fuel type can be used to tailor the combustion performance and the structural properties of the nano-composite thermites containing iron oxide xerogel.