Solvothermal Synthesis And Properties Of Open-framework Cobalt Phosphites

Inorganic microporous materials have popular applications in catalysis, adsorption, ion-exchange, separation and host-guest assemblies due to their unique pore architectures, thus the rational design and synthesis of new microporous compounds, as well as the development of new synthetic ways are becoming the central topic of microporous materials chemistry. Zeolites (aluminosilicates) are the most well-known microporous molecular sieves. During the past decades, a huge number of new zeolite-like inorganic solids like phosphates, arsenates, germanates, phosphite, sulfate, selenite, carbonate have been synthesized and characterized. The successful syntheses of these new compounds with open-framework open a new field for the microporous compounds.In this paper, we have obtained three cobalt phosphite compounds (1-3) and one zinc phosphite compound (4) by using template or structural directing agent under the solvothermal conditions . The main results are as follow:Compound (C4H12N2)[Co(HPO3)2] (1) possesses a 1D chain-like structure, containing corner-shared (cs) four-membered rings constructed from CoO4 tetrahedral and HPO3 pseudo-pyramid.Compound [C4H12N2]0.5[(CH3)2NH2][Co2(HPO3) 3] (2) exhibits a 2D layered structure with 4- and 12-rings, where diprotonated PIP molecules occupy the middle of 12-ring windows, and protonated dimethylamine molecules (coming from the decomposition of DMF) reside between the two layers, through the H-bond interacting with the inorganic framework.Compounds [C2H8N]2[Co3(HPO3)4] (3) exhibits a 3D open-framework with intersecting 16-membered ring channels. The structure of compound 3 consists of 1D ladder-like chains formed by alternating ZnO4 tetrahedra and HPO3 pseudo-pyramids, which are further linked through cobalt atom giving rise to a 3D open-framework Compound (C2H3N3)Zn(HPO3) (4) exhibits 2D layered structure with 4.8-net. The structure of compoud 4 consists of left-handed and right-handed helical chains that are connected through bridging oxygen atoms to form a two dimensional layer structure.