Insights into thermochemistry, kinetics, and pyrolysis behavior of green gas generator 5- aminotetrazole by experiment and theoretical methods

Green gas generator 5-aminotetrazole(5-AT) has been widely used as a kind of energetic material with excellent properties, and it is crucial to understand its pyrolysis process and mechanism. The present study comprehensively investigated the thermochemistry, kinetics, and pyrolysis mechanism of green gas generator 5-AT, using a combination of experimental analysis and theoretical calculation. Thermogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FTIR) were used to investigate the pyrolysis behavior of 5AT and energy barriers of transition states for different pyrolysis paths of three isomers of 5AT were also calculated at a high and reliable level of theory CCSD(T)/cc-pvtz. The results showed that the pyrolysis of 5-AT had five reaction stages and kinetic parameters in each stage were determined by Kissinger method and Criado method. Furthermore, the elimination of N2 from the tetrazole ring occurred before that of HN3, and N2 elimination had lower energy than HN3 elimination for 1-hydrogen-5-aminotetrazole and 2-hydrogen-5-aminotetrazole, but HN3 elimination had lower energy for 5-iminotetrazole. The results of the study provide useful insights into the pyrolysis mechanism and kinetics of 5-AT and could contribute to its efficient utilization in various applications.