In situ synthesis of chromium carbide nanocomposites from solution combustion synthesis precursors

Chromium carbide nanocomposites were in situ synthesized by combing solution combustion synthesis method and carbothermal reduction for the first time. A homogeneous precursor (amorphous chromium oxide and carbon) was fabricated by solution combustion synthesis method using glucose, chromium nitrate and glycine as raw materials. The precursor powders were subsequently reduced under nitrogen at 600-900 degrees C for 1 h. The combustion synthesis process and carbothermal reduction process were studied in detail. The products were analyzed by X-ray diffraction, scanning electron microscope and energy dispersive spectrometer, field-emission electron microscope, transmission electron microscopy, high-resolution transmission electron microscopy and Raman spectrometer. The results indicated the chromium carbide nanorods with well crystalline structure were successfully in situ synthesized at low temperature (700 degrees C) without any catalyst. When further improved the temperature, the carbon in the products transformed into graphite and chromium carbide is gonging to allotropic transformation. Furthermore, it can prepare graphite based nanosheet composites at lower temperatures (900 degrees C). (C) 2018 Elsevier B.V. All rights reserved.