Porphyrinylphosphonate‐Based Metal–Organic Framework: Tuning Proton Conductivity by Ligand Design
Yulia Yu. Enakieva, Anna А. Sinelshchikova, Mikhail S. Grigoriev, Владимир В. Чернышев, Konstantin A. Kovalenko, И. А. Стенина, A. B. Yaroslavtsev, Yulia G. Gorbunova, А. Yu. Tsivadze
Abstract
Abstract A novel metal–organic framework [Zn 3 (Ni‐H 2 TPPP)(Ni‐H 4 TPPP)(Ni‐H 5 TPPP) ⋅ 7(CH 3 ) 2 NH 2 ⋅ DMF ⋅ 7 H 2 O] (where Ni‐H x TPPP ( x= 2,4,5) are partially deprotonated [5,10,15,20‐tetrakis(3‐(phosphonatophenyl)‐porphyrinato(2‐))]nickel(II) species), IPCE‐2Ni , with outstanding proton conductivity (1.0×10 −2 S cm −1 at 75 °C and 95 % relative humidity) has been obtained. The high concentration of free phosphonate groups and compensating dimethylammonium cations bound by hydrogen bonds in the unique crystal structure of IPCE‐2Ni is a key factor responsible for the observed high proton conductivity, which is one order of magnitude higher than for the corresponding MOF based on 5,10,15,20‐tetrakis(4‐(phosphonatophenyl)porphyrinato(2‐))]nickel(II) IPCE‐1Ni and comparable with that of leaders among MOFs.