Sonochemical combustion synthesis of purer Ti2AlC from Ti-Al-C system

Conventional combustion synthesis (CS) reaction has been widely used in the production of compounds. Obtaining pure products, however, is always a challenge for the CS reaction. This research proposed an effective method by adding ultrasound to the CS reaction to improve the purity of the products, in which Ti-Al-C with a molar ratio of Ti:Al:C = 2:1:1 was used as a reactive system. Experimental results showed that Ti3AlC2 was the main ternary carbide rather than Ti2AlC in the control sample without ultrasonic treatment, while Ti2AlC dominated in the ultrasonically treated sample. Our research indicated that Ti3AlC2 could be formed more easily than Ti2AlC in the special CS environment from a thermodynamic perspective. Ultrasound-induced sonochemical effects could create a more homogeneous formation environment for Ti2AlC and a kinetic promotion for synthesizing Ti2AlC was realized in the CS reaction. Driven by the ultrasound, the yield of Ti2AlC could be dramatically enhanced. In addition, the combination of ultrasound and the CS reaction provided a simple and effective approach for synthesizing other advanced materials.