Thermal decomposition of ammonium perchlorate/exfoliated-graphene and the relationship between activation energy and band gap Article uri icon

abstract

  • The thermal decomposition of ammonium perchlorate AP with electrochemically exfoliated graphene flakes (EGF) was studied at different heating rates in nitrogen and the combustion behavior of AP/EGF propellant was evaluated. The exothermic reaction kinetics were studied by simultaneous thermal analysis (STA) in non-isothermal conditions and compare with the thermal decomposition of pure AP applying the same experimental conditions. Using the Kissinger method, the calculated activation energies Ea for the low- and high-temperature exothermic reactions were 87 and 198 kJ/mol for pure AP, contrasting with 91 and 55 kJ/mol obtained from AP with 5 wt%25 EGF. From our experimental activation energy values together with reported and calculated band gaps Eg, it was found the empirical relationship: (Formula presented.) where Ea0 corresponds to the activation energy associated with the high-temperature thermal decomposition of pure AP, Eac is the activation energy associated to the high-temperature thermal decomposition of AP-EGF, E0 = 2.7 eV is the catalyst band gap threshold required to activate the electron transfer mechanism and n = 6 is the exponential factor associated to pure AP. © 2019, © 2019 Taylor %26 Francis Group, LLC.

publication date

  • 2019-01-01