Self-adjusted synthesis of ordered stable mesoporous minerals by acid-base pairs.

Abstract

Although the chemical diversity of ordered composite mesoporous materials has been expanding during the past decade, progress has been limited by the need for a general synthetic approach that is predictive and makes use of well developed fundamental chemical principles. Researchers have previously used the interaction of organic-inorganic (OI) species that are present during the nucleation of the composite phase, and several synthesis pathways, such as direct surfactant-inorganic interaction (S+I-, S-I+, S0I0) and mediated interaction (S+X-I+, S-X+I-), have been proposed. Here we describe a new perspective in which the self-adjusted inorganic-inorganic (II) interplay between two or more inorganic precursors is guided by acid-base chemistry considerations, and in this simple way we produce an overall 'framework' for the sophisticated combination of synergic inorganic acid-base precursor pairs. We propose several new routes and demonstrate their versatility and validity through the successful syntheses of a wide variety of highly ordered, large-pore, homogeneous, stable and multicomponent mesostructured minerals, including metal phosphates and metal borates, as well as various metal oxides and mixed metal oxides. We show that the highly ordered mesostructured metal phosphates can be moulded into morphologies of choice, and that they show interesting physicochemical properties.