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.