Features of thermolysis of Cr (III) aromatic carboxylates

The article discusses the main methods for obtaining carbon composite nanomaterials and highlights the thermolysis method as one of the main methods. To understand the essence of thermal decomposition processes as a method for synthesis of carbon nanomaterials, chromium (III) aromatic carboxylates have been considered. These are chromium (III) 8-hydroxyquinolinate, benzoate, salicylate, phthalate, and p -aminobenzoate. The article thoroughly discusses the procedure for the synthesis of these chromium (III) carboxylates from the most common inorganic chromium (III) salts under simple conditions. The thermal decomposition process was carried out in two environments (in oxidizing air and neutral argon), the obtained products were compared. For a detailed study of the processes of decomposition of chromium (III) carboxylates, thermal analysis methods (TG and DSC) were used on a Netzsch 449 Jupiter synchronous thermal analyzer. To study the morphology and composition of the products, the methods of X-ray phase analysis, optical and scanning electron microscopy, and X-ray fluorescence microanalysis were used. We used a Rigaku Ultima IV X-ray diffractometer and a scanning electron microscope with a Jeol JSM-7001F elemental microanalysis attachment. On the basis of the obtained results, the estimated formulas of the initial chromium (III) carboxylates were calculated. The mechanisms of the processes occurring during the thermal decomposition of chromium (III) aromatic carboxylates were also proposed. For a more accurate determination of the composition of the synthesized chromium (III) carboxylates and a more accurate description of the processes of thermal decomposition of these salts, the corresponding aromatic carboxylic acids were also subjected to thermal decomposition. The appendix to the article contains all the obtained data for a more accurate interpretation of the results and a more detailed description of the thermal decomposition processes.