Preparation of flower-like CdO microspheres and its catalytic performances towards thermal decomposition of ammonium perchlorate

Abstract

A two-step method involving solvothermal synthesis and annealing was used to prepare the flower-like CdO microspheres.The flower-like precursor microspheres assembled by nano-flakes were firstly fabricated by the solvothermal method using Cd(Ac)2 as source materials in methanol system.Through calcining the precursor,CdO porous microspheres with well-preserved morphologies were then obtained.X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR), thermal gravimetry(TG),scanning electron microscopy(SEM),transmission electron microscopy(TEM) and N2 adsorption-desorption were used to characterize the phases,chemical composition,morphologies and pore structures of the samples.Differential scanning calorimetry(DSC) was employed to evaluate the catalytic performance of these CdO microspheres for thermal decomposition of ammonium perchlorate(AP).The results show that the as-obtained CdO microspheres play a positive role in catalyzing the thermal decomposition of AP.Adding 2%(mass fraction)CdO microspheres into AP,the peak temperature decreases from 444.4 ℃ to 402.8 ℃ and the heat released increases from 586.9 J/g to 1091.7 J/g.The activation energy of AP decomposition significantly decreases from 280.5 kJ/mol to 83.78 kJ/mol.Based on the results, a possible catalytic mechanism for the thermal decomposition of AP over flower-like CdO microspheres is proposed.

Keywords

• cadmium oxide
• flower-like microsphere
• ammonium perchlorate
• thermal decomposition
• cata- lytic performance