A novel 2D coordination network built from hexacopper(i)-iodide clusters and cagelike aminophosphine blocks for reversible “turn-on” sensing of aniline

Abstract

A new copper(I) coordination polymer [Cu₆(μ₃-I)₆(μ₃-PTAO)₂]_n (1) was prepared from copper(I) iodide and 1,3,5-triaza-7-phosphaadamantane-7-oxide (PTAO). The crystal structure of 1 reveals an intricate 2D coordination network constructed from the hexacopper(I)-iodide [Cu₆(μ₃-I)₆] cluster units with the 4M6-1 topology interlinked by the μ₃-PTAO spacers. An overall 2D layer network can be simplified to a binodal 3,6-connected net with the kgd topology. A derived 1@paper material was prepared by impregnating compound 1 onto a filter paper. Detailed investigation of the luminescence properties for 1 and 1@paper in the solid state revealed a remarkable ability of both materials to sense aniline molecules in liquid and vapor phases at room temperature. The visibility to the naked eye and the reversible color response of 1 and 1@paper upon contact with aniline make these materials rather promising candidates for application as “turn-on” luminescence sensors for aniline recognition at room temperature. Visual aniline sensing detection limits of 0.26 and 0.065 ppb were observed for 1 and 1@paper under ambient conditions, respectively.