The phase and morphological evolution of Ti3SiC2 MAX phase powder after HF treatment

The aim of this study is to investigate the phase and morphological evolution of the prepared Ti3SiC2 MAX phase powder after immersion in hydrofluoric acid (HF) solution for 24, 72, 96 and 120 h. The phase and morphological evolution of Ti3SiC2 was analyzed using X-ray diffraction (XRD) patterns, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). XRD results revealed that after 24 h HF treatment the diffraction peaks of Ti3SiC2 were fully disappeared and this treatment led to the decomposition of Ti3SiC2 to TiC. XRD and EDS findings demonstrated that de-intercalation of Si layer occurred after HF treatment. Moreover, SEM images showed that the morphological shape of TiC particles significantly changed as a function of HF treatment times. In summary, the shape of TiC particles changed from the polyhedron to hexagonal, then to truncated octahedron, octahedron and cubic.