Thermal decomposition of ammonium perchlorate in the presence of Cu(OH)2·2Cr(OH)3 nanoparticles

Abstract

The Cu(OH)2·2Cr(OH)3 nanoparticle preparation procedure and its accelerating effect and accelerating mechanism on thermal decomposition of ammonium perchlorate (AP) were investigated using transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), selected area electron diffraction (SAED), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis and differential scanning calorimetry (TG–DSC), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis and mass spectroscopy (TG-MS). In the preparation procedure, TEM, SAED, and EDS showed that the Cu(OH)2·2Cr(OH)3 particles were amorphous with nanometer size under the controllable preparation conditions. When the amorphous Cu(OH)2·2Cr(OH)3 nanoparticles were used as additives for the thermal decomposition of AP, the TG–DSC results showed that the addition of Cu(OH)2·2Cr(OH)3 nanoparticles to AP remarkably decreased the onset temperature of AP decomposition from approximately 450°C to 259°C. The XRD and FT-IR results confirmed that the Cu(OH)2·2Cr(OH)3 nanoparticles were transformed from amorphous form to Cr2O3 and CuCr2O4 phases after being used as additives for the AP thermal decomposition. The XPS results indicated that Cu2+ of the Cu(OH)2·2Cr(OH)3 surface gained the electron from the perchlorate ion of AP, and the Cu ions were enriched on the Cu(OH)2·2Cr(OH)3 surface in the AP decomposition. The electron transfer process plays a major role in the decrease of the onset temperature of AP decomposition, while the nano-effect is beneficial to easier enrichment of Cu ions on the surface of Cu(OH)2·2Cr(OH)3 nanoparticles.