L10 CoPt nanoparticles with face-centred tetragonal (FCT) structure are synthesized by the sol–gel method. Differential thermal analyses show the dehydration of various water molecules and decomposition/combustion of organic groups at a temperature below 600 °C and melting of Co and Pt at 700 °C. X-ray diffraction results show a transition from face-centred cubic to the FCT phase and an increase in particle size with increasing temperature. Transmission electron microscope (TEM) images show that highly monodisperse particles are obtained. High-resolution TEM (HRTEM) images reveal the appearance of L10 ordered phase at temperatures above 600 °C. The survey scans of x-ray photoelectron spectroscopy show that no magnetic impurity is detected within the detection limit. The maximum coercivity (353 344 A m−1) is obtained for the samples heated at 800 °C. The relationship between the temperature and the structure is discussed and the possible growth mechanism is given in terms of atomic diffusion.

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The introduction of carbon nanotubes (CNTs) in the preparation of nano-lead oxide (PbO) can effectively solve the problem of easy agglomeration of nano-lead oxide. This study used concentrated nitric acid and concentrated sulfuric acid mixed acid (volume ratio 1:3) to oxidize carbon nanotubes at 90 °C temperature for 0.5 h. Using and the oxidized CNTs as carriers, Pb(OAc)2 · 3H2O as precursor, concentrated ammonia as a precipitator, PbO/CNTs complexes were prepared by chemical precipitation. Lead content of PbO/CNTs complex, determined by Complexometry, was 59.80 %(wt%), XRD and XPS characterizations revealed that the catalyst components of the prepared complex were mainly nano-sized PbO, And a small amount of lead, SEM and EDX characterization revealed PbO with the particle size between 20 m-200 nm had been successfully Loaded onto the CNTs surface, TEM show that the PbO and CNTS retained the original lattice, a spot of lead oxide was found inside the tubes. The thermal decomposition effect of PbO/CNTs on AP, RDX, HMX was evaluated by DSC, and the catalytic effect on AP and RDX was found to be obvious.