A Comprehensive Scenario of the Crystal Growth of γ-Bi2MoO6 Catalyst during Hydrothermal Synthesis

In a previous study, we confirmed by in situ combined high-resolution powder diffraction/X-ray absorption spectroscopy and Raman scattering experiments that the crystal formation of the well-known gamma-Bi2MoO6 catalyst occurred in two steps through the formation of an intermediate fluorite structure (Kongmark, C. et al. Chem. Commun. 2009, 4850-4852; Catal. Today 2010, 157, 257-262). Here, for the first time, by combining these results with complementary ex situ studies (HTXRD, SEM/EDX, Raman scattering), it was possible to elucidate the nature of the intermediate phase and to propose a complete scenario of the growth of gamma-Bi2MoO6 crystals. In addition, we performed a kinetic analysis from the three different in situ characterization techniques and confirmed a 2D-diffusion limited growth process.