Bifunctional Metal–Organic Framework Functionalized by Dimethylamine Cations: Proton Conduction and Iodine Vapor Adsorption

A metal–organic framework, {Zn3(BTB)2(μ3-OH)[(CH3)2NH2](H2O)}n (1), was synthesized based on H3BTB (1,3,5-tri(4-carboxyphenyl)benzene). An AC impedance test proves that 1 has a relatively high conductivity performance of 1.52 × 10–3 S·cm–1 at 338 K and 98% RH. The proton conductivity of the composite film 1@CS-9 (CS = chitosan) reaches 1.84 × 10–1 S·cm–1 at 328 K and 98% RH. In addition, 1 is discovered to have a good adsorption effect on iodine vapor, and the adsorption capacity reaches 726 mg·g–1. The multifunctionality caused by dimethylamine cations was investigated for the first time, which has implications for multifunctionality generated by host–guest molecules.