Kinetics of aluminum extraction from Ti3AlC2 in hydrofluoric acid

Abstract

Herein we report on the influence of particle size, time and temperature on the kinetics-quantified by X-ray diffraction-of the selective extraction of Al from the ternary layered transition metal carbide, Ti3AlC 2, when powders of the latter are immersed in hydrofluoric acid. Transmission and scanning electron microscopy, energy-dispersive X-ray spectroscopy and thermogravimetric analysis were also used to characterize the resulting powders. Increasing the temperature and immersion times, and decreasing the Ti3AlC2 particle size, led to faster conversion of Ti3AlC2 to its 2-D Ti3C 2 counterpart. Arch-shaped edges at the ends of some Ti 3C2 layers resembled graphene, corroborating the single-sheet structure of exfoliated Ti3C2. The removal of water and/or OH surface groups from Ti3C2 using drying in vacuum was also attempted. © 2013 Elsevier B.V. All rights reserved.