New Insights into the Catalytic Decomposition of Ammonium Perchlorate and Decomposition Mechanism by Nano-CuO Dispersed in Graphite-Carbon Nitride Nanosheet Composites

Enhancing the exothermic decomposition of ammonium perchlorate (AP) is of great significance to obtain solid propellants with excellent combustion performance. Herein, we prepared a series of composites for catalyzing the exothermic decomposition of AP by a facile method with different masses of nano copper oxide (n-CuO) dispersed in graphene-nitride carbon (g-C3N4) nanosheets. Among them, n-CuO-8/g-C3N4 showed the best catalytic activity, which reduced the high-temperature decomposition (HTD) value by 95.0 degrees C, and increased the total heat release by 505 J.g(-1). The n-CuO-12/g-C3N4 also reduced the activation energy (E-a) of the HTD stage by 47.34 kJ.mol(-1). The catalytic mechanism study suggested that the n-CuO-X/g-C3N4 composites promoted the transition of electrons (e(-)) and holes (h(+)) from ClO4- to NH4+ and inhibited the recombination of e(-) and h(+), which further enhanced the exothermic decomposition of AP. During decomposition, the transformation of N2O to NO was significantly inhibited by the n-CuO-X/g-C3N4 composites, thus increasing the integral heat release as evidenced by Real-time thermogravimetry/Fourier transform infrared spectroscopy. This study illustrated that n-CuO-X/g-C3N4 composites are catalysts for the efficient decomposition of AP, which further enhance the energy performance of solid propellants.