LAUSR

Two novel 3D metal-organic frameworks (MOFs) with cds network, {[MeNH3]7[Ln8(PgC2)2(H2O)y(HCOO)7]}n·x(Solvent) (FJIY4, FJI=Fujian Institute, Ln=Gd, y=12; FJI-Y5, Ln=Dy, y=11; PgC2=C-ethylpyrogallol[4]arene), based on unprecedented dimeric pyrogallol[4]arene-based Ln8 metal-organic nanocapsule (MONC) supramolecular building blocks and formate linkers, have been prepared under solvothermal conditions. To our best of knowledge, they present not only the first two examples of 3D hierarchical structures constructed from MONCs in metal-pyrogallol[4]arene system, but also the first two examples of MOFs based on lanthanide MONCs. Remarkably, the inner cavity volume of the Ln8 capsule in FJI-Y4 and FJI-Y5 is approximately 151 Å3, which is larger than those found in previous transition metal-seamed dimeric PgCn-based MONCs. Magnetic investigation on FJI-Y4 suggests a significant magnetocaloric effect (23.97 J kg−1 K−1, ΔH=7 T, 2.5 K), while FJI-Y5 exhibits slow relaxation of the magnetization.