Synthesis and structural stability of Ti2GeC

In this paper we report the synthesis of a ternary-layered ceramic, Ti2GeC, a 211 Mn+1AXn compound by hot-pressing. X-ray analysis confirmed the hexagonal crystal symmetry. Using a synchrotron radiation and a diamond anvil cell, we measured the pressure dependencies of the lattice parameters. The phase is structurally stable up to the 49 GPa—the maximum experimental pressure reached. The bulk modulus of Ti2GeC calculated using the Birch-Murnaghan equation of state is 211 ± 4 GPa with K′ = 3.9 ± 0.2. Surprisingly the bulk modulus was found to be greater than both Ti2AlC and Ti2SC by 13% and 10%. Also, Ti2GeC has the highest bulk modulus among M2GeC phases where M = Ti, V, Cr.