An Organo-templated Iron Zincophosphate with Zeolite DFT Topology

Abstract

The synthesis and application of open-structured materials are an active area of solid-state chemistry research due to their specific properties such as catalytic, ion exchange and intercalation. After the successful synthesis of aluminophosphates, templated metal phosphates with open-framework have been extensively studied to discover new architectures and compositions. Among the open-framework phosphates, the zincophosphates are the second largest family that have been studied in the past decade. Since the first zincophosphate with zeolite topologies reported by Stucky and co-workers, a great deal of effort has been devoted to the pursuit of novel structures within this system. Their structures consist of vertex-sharing networks of ZnO4 and PO4 tetrahedra, corresponding to anionic framework [ZnPO4−], that are equivalents to those encountered in aluminosilicates of composition [AlSiO4−]. Zincophosphates with zero-, one-, twoand three-dimensional architectures have been isolated. A large number of iron phosphates have also been synthesized in the past ten years. Probably, the most striking example of this family is the mineral cacoxenite that contains cylindrical tunnels of 14.2 A. Another goal is incorporation of active metals into known phases to improve their catalytic properties. Transition metal substituted aluminophosphates are successful examples of this approach and have given rise to some new topologies. Iron incorporated open-framework materials have shown interesting catalytic performances. However, there is no example of open-framework compound that has both iron and zinc. Such materials may be interesting in view of developing new catalysts. Previously, we have synthesized several zincophosphates and bimetallic phosphates. In this study, we have explored the iron zinc phosphate system and synthesized [Fe0.4Zn0.6PO4]2· [NH3CH2CH2NH3] (1). Compound 1 is a structural analogue with the zeolite DFT topology. To our knowledge, transition metal phosphates with zeolitic topologies are seldom in the literature. Here we report its synthesis and structure.