Three Coordination Polymers Based on 1H-Tetrazole (HTz) Generated via in Situ Decarboxylation: Synthesis, Structures, and Selective Gas Adsorption Properties

Three tetrazole-based coordination polymers, [Zn3(Tz)6(H2O)2]n (1), [Cu2(Tz)3(OH)]n (2), and {[Cu5(Tz)9](NO3)·8H2O}n (3) (Tz = tetrazolate) have been prepared under hydro(solvo)thermal conditions using ethyl tetrazolate-5-carboxylate and corresponding metal salts as building blocks, in which tetrazolate was generated via in situ decarboxylation. The results of X-ray single diffraction analyses indicate that 1 possesses a 2D layer structure with μ2-Tz− bridged six- and four-coordinated Zn(II), forming a rare kagomé dual topological layer. Compound 2 is a 3D layer−pillar structure, in which the Cu(II) ions are bridged by μ3-Tz− anions to generate a 2D sheet, and the 2D sheets are further pillared by μ2-Tz− and μ2-OH− to form a 3D framework with a fsc topology net. Compound 3 is a 3D porous framework with an acs topology net. Compound 1 exhibits photoluminescent properties with an emission peak at 467 nm, and compound 3 shows selective H2 and CO2 over N2 adsorption.