Djamel Eddine Kadri

Bio: Djamel Eddine Kadri is an academic researcher from École Normale Supérieure. The author has contributed to research in topics: Thermal decomposition & Differential scanning calorimetry. The author has co-authored 1 publications.

Preparation of different morphology Cu/GO nanocomposites and their catalytic performance for thermal decomposition of ammonium perchlorate

Abstract: Cu nanoparticles are more active catalytically than CuO nanoparticles, which have been widely studied as catalysts for organic synthesis, electrochemistry, and optics. However, Cu nanoparticles are easily agglomerated and oxidized in air. In this research, columnar, flower-like, bubble-like and teardrop-shaped Cu/GO nanocomposites were fabricated via a water-solvent thermal method and high temperature calcination technique using deionized water (H2O), methanol (CH3OH), ethanol (CH3CH2OH) and ethylene glycol (EG) as the solvent, respectively. The structures, the morphology and the catalytic performance and catalytic mechanism for thermal decomposition of ammonium perchlorate (AP) of the Cu/GO nanocomposites have been studied by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), nitrogen adsorption tests (BET), simultaneous thermogravimetry-differential scanning calorimetry (TGA/DSC) and thermogravimetric couplet with Fourier transform infrared spectroscopy (TGA–FTIR), respectively. The experimental results show that the morphology of the Cu/GO nanocomposites has a significant effect on the surface area and the teardrop-shaped Cu/GO nanocomposites have the largest specific surface area and the best catalytic performance among them. When 5 wt% of the Cu/GO nanocomposites was added, the decomposition temperature of AP decreased from 426.3 °C to 345.5 °C and the exothermic heat released from the decomposition of AP increased from 410.4 J g−1 to 4159.4 J g−1. In addition, the four morphological Cu/GO nanocomposites exhibited good stability, their catalytic performance for thermal decomposition of AP remained stable after 1 month in air. Excellent catalytic performance and stability were attributed to the strong catalytic activity of pure metal nanoparticles, and GO can accelerate electron movement and inhibit the agglomeration of nanoparticles, as well as the multiple effects of inhibiting the oxidation of Cu nanoparticles in air. Therefore, it has important application potential in high-energy solid propellant.

Thermal behavior and kinetics of double base propellant catalyzed with green graphene iron oxide nanocomposite

Abstract: In this work, a green approach for the synthesis of graphene-iron oxide nanocomposite (GINC) was followed. FTIR, Raman, XRD and SEM analysis tools were all used to characterize the synthesized nanocomposite. Furthermore, the Differential Scanning Calorimetry (DSC) method was used to investigate the GINC's catalytic activity for the decomposition of a double base propellant (DBP). Kinetic characteristics for the thermal decomposition of DBP such as activation energy and frequency factor, were determined using iso-conversional approaches, including Vyazovkin's nonlinear integral with compensatory effect (VYA/CE), iterative Kissinger–Akahira–Sunose (It-KAS), and iterative Flynn–Wall–Ozawa (It-FWO). Based on the results obtained from the kinetic analysis, the introduction of GINC has reduced the activation energy of the pristine DBP (approximately 230 kJ/mol) by 40 kJ/mol, showing that this addition has good catalytic activity on the thermal degradation of DBP. Additionally, the results showed that the critical ignition temperature is augmented from 187.1 to 199.6 °C, when DBP is doped with 3% GINC highlighting the fact that GINC enhanced the thermal safety of DBP.

Copper Complexes in Carbon Nanotubes as Catalysts for Thermal Decomposition of Energetic Oxidizers

Abstract: Metal compounds exhibit high catalytic activities in solid propellants as burning rate catalysts (BRCs), while the bulk particles and the nanoparticles loaded onto the surfaces of carbon materials cannot effectively display their catalytic activities. For reducing particle aggregation and improving their catalytic efficiencies as BRCs, seven copper complexes (CuL2) were successfully encapsulated into the inner spaces of carbon nanotubes (CNTs) via ultrasonication in this study. These complexes include Cu(Sal)2 (Sal = salicylate), CuC2O4, Cu(NO3)2·3H2O, Cu(acac)2 (acac = acetylacetonate), [Cu(TMEDA)2](NO3)2 (TMEDA = tetramethylethylenediamine), [Cu(MIM)4](DCA)2 (MIM = 1-methylimidazole, DCA = dicyanamide), and [Cu(NMIM)4](DCA)2 (NMIM = 1-methyl-2-nitroimidazole). In addition, the structures of the CuL2@CNT nanocomposites were investigated using transmission electron microscopy, scanning electron microscopy, Brunauer–Emmett–Teller surface area analysis, X-ray photoelectron spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and X-ray diffraction. Moreover, the combustion catalytic performances of the nanocomposites in the thermal decomposition of ammonium perchlorate (AP), cyclotrimethylenetrinitramine (also known as RDX), and 1,1-diamino-2,2-dinitroethene were evaluated; these performances considerably affect the thermal degradation of AP and RDX. The 5 wt % Cu(acac)2@CNTs with outer diameters of 4–6 nm (L1) caused the peak temperature of AP to shift 92.8 °C toward left at the high-temperature decomposition stage, and the released heat increased by 1448.06 J g–1 compared to pure AP; the 5 wt % [Cu(NMIM)2](NO3)2/@CNT (L1) advanced the RDX peak temperature by 17.3 °C. Moreover, the thermal decomposition mechanism of RDX in the presence of Cu(acac)2@CNT (L1) was investigated via in situ solid FTIR and thermogravimetry–FTIR–mass spectrometry. The additive (CuL2@CNTs) accelerated the exothermic reaction of C–N bond breakage. This in turn reduced the endothermic reaction of the N–N bond cleavage in RDX, contributing to an increase in the heat released by RDX. Based on these results, a potential mechanism is proposed where RDX pyrolysis is catalyzed by the composites.