In-Situ Growth of ZnO Whiskers on Ti₂ZnC MAX Phases

ZnO whiskers have many applications, such as in medical and photocatalysis fields. In this study, an unconventional preparation approach is reported, realizing the in-situ growth of ZnO whiskers on Ti₂ZnC. The weak bonding between the layer of Ti₆C-octahedron and the Zn-atom layers leads to the easy extraction of Zn atoms from Ti₂ZnC lattice points, resulting in the formation of ZnO whiskers on the Ti₂ZnC surface. This is the first time that ZnO whiskers have been found to grow in-situ on Ti₂ZnC substrate. Further, this phenomenon is amplified when the size of the Ti₂ZnC grains is mechanically reduced by ball-milling, which bodes a promising route to prepare ZnO in-situ on a large scale. Additionally, this finding can also help us better understand the stability of Ti₂ZnC and the whiskering mechanism of MAX phases.