5-aminotetrazole (5AT)-based gas generators, particularly the 5AT/NaIO4 system, have garnered interest for their high gas production and energy potential. This study investigates the impact of various metal oxides (MnO2, Al2O3, TiO2, CuO, Fe2O3, MgO, ZnO, and MoO3) on the thermal decomposition and combustion performance of 5AT/NaIO4. The REAL calculation program was used to infer reaction products, which indicated that the gas products are almost all harmless, with negligibly low percentages of NO and CO. Thermogravimetric analysis revealed that metal oxides, especially MoO3, significantly advance the decomposition process above 400 degrees C, reducing the activation energy by 130 kJ/mol and lowering critical ignition and thermal explosion temperatures. Combustion performance tests and closed bomb tests confirmed MoO3's positive effect, accelerating reaction rates and enhancing decomposition efficiency. The system's high Gibbs free energy indicates non-spontaneous reactions. These findings provide valuable insights for designing environmentally friendly gas generators, highlighting MoO3's potential as an effective catalyst.