Fig. 2: Synthesis routes of λ-MxTi3-xO5 and the phase transition mechanism from the λ to the β phase.
From: Sub-minute synthesis and modulation of β/λ-MxTi3-xO5 ceramics towards accessible heat storage
a The routes for synthesizing room temperature stable λ-MxTi3-xO5 with different metal substitutions: Route I: laser-assisted vacuum decomposition, TiO2 + MO → λ-MxTi3-xO5 + O2 (M = Al or Sc); Route II: laser-assisted melting, β-Ti3O5 + MO → λ-MxTi3-xO5 (M = Al, Sc, Mg, V, Cr, Mn, or Fe). The insets are the structures of anatase-TiO2 and β-Ti3O5. b The energy barriers for the transition from the λ-phase to the β-phase using the density functional theory (DFT) calculations. The insets are the structures of the λ-phase, the transition state, and the β-phase. c The energy barriers for the transition from the λλ-phase to the ββ-phase of λ-AlxTi3-xO5 using the density functional theory (DFT) calculations. The insets are the structures of λ-AlxTi3-xO5, the λβ stacking metastable phase, and β-AlxTi3-xO5.
