Template Effect of Chain-Type Polyamines on Pore Augmentation: Five Open-Framework Zinc Phosphates with 16-Ring Channels

Abstract

Five new zinc phosphates with differently unique 3D framework topologies, (H3dien)[Zn3(HPO4)3(PO4)] (1), (H2dien)1.5[Zn3(HPO4)3(PO4)] (2), (H3dien)[Zn3(H2PO4)(HPO4)(PO4)2] (3), (H3dien)[Zn3(HPO4)3(PO4)]·1.5H2O (4), and (H4tepa)0.5[Zn2.5(HPO4)2(PO4)]·1.5H2O (5), where dien = H2NC2H4NHC2H4NH2 and tepa = H2N(C2H4NH)3C2H4NH2, have been synthesized under mild hydrothermal or solvothermal conditions and characterized by single-crystal X-ray diffraction, thermal analysis, solid-state NMR, UV–vis, or photoluminescence spectroscopy. Both the 7-atom-skeleton-long dien and the 13-atom-skeleton-long tepa have created 16-membered ring (16R) channels as a common feature in structures 1–5. Their inorganic frameworks are built up with tetrahedra of ZnO4, PO4, and HPO4 (plus H2PO4 in 3) and may all be described as constructed from two-dimensional nets and one- or zero-dimensional units as linkers. Compounds 1–4 have the same Zn/P ratio but possess varied amount of nonframework volume. They are the first examples with dien as template in extra-large-channel structures of zincophosphates. In comparison, the framework of 5 contains a higher value in Zn/P and larger nonframework volume than that in the 24R-channel structure of ND-1. The 16R channels in 1 and 2 are one-dimensional while those in 3, 4, and 5 are unprecedentedly two-dimensional. In this paper, the synthesis, thermal property, NMR, reflectance UV–vis absorption, and photoluminescence study of 1–5 are described; framework topologies, structure relationship, the charge and location of templates, and channel characteristic vs nonframework volume are discussed.

Synthesis, Structure, and Polymorphism Studies in Amine-Templated Open-Framework Zinc Phosphites

“…The literature abounds with report of many open-framework structured materials prepared using a variety of organic amines as structure-directing agents. ,, There have been some studies on the use of a single amine for preparing a number of different structures . Recently, Wang and co-workers have shown that it is possible to prepare different zinc phosphate phases using the organic amine DETA which has already been shown to give rise to three different zinc phosphate phases . In all these studies, there has been no correlation between the starting synthesis composition and the final solid product.…”

Small organic amine assisted synthesis of an extra-large pore containing open-framework zinc-cobalt phosphate templated by a chain-type polyamine

“…It has once been reported that a ZnPO 4 with the same structure of CoZnPO 4 -V was obtained previously. However, the quality of the crystals of this ZnPO 4 was always too poor to give better refinement results [5] . In our research, both the zinc-cobalt composition in the framework and the presence of small amines as the assistant organics play a key role in the growth of the perfect crystal.…”

“…Among the increasingly synthesized frameworks, the system of metal phosphates and phosphites has shown a greater disposition to form extra-large-pore structures [5][6][7][8] . Up to now, almost all the largest channel (including 24-ring and 26-ring) frameworks have been obtained in phosphates and phosphites [9][10][11][12] .…”

New Crystalline Layered Zinc Phosphate with 10-Membered-Ring Channels Perpendicular to Layers

“…Zincophosphates are an important subset of the large phosphate family. Although over 20 different zincophosphates with various structural dimensionalities and stoichiometries have been synthesized and characterized, − the preparation of zinc phosphates with novel structures is still possible. − Most of these structures are built up from vertex-linked ZnO 4 and PO 4 tetrahedra, and connectivity between two or more ZnO 4 tetrahedra through Zn−O−Zn linkages is rare . These materials are typically synthesized hydrothermally using a zinc salt and phosphoric acid, together with an organic amine acting as a template or structure-directing agent.…”