Framework-Isomeric Metal–Organic Frameworks Built from Supermolecular Building Blocks for High Iodine Capture

The supermolecular building block approach is powerful
in constructing
hierarchically porous metal–organic frameworks (MOFs). However,
the structural diversity of these extended frameworks built from the
same building blocks has never been explored. Herein, we propose a
strategy by synergistically tuning the extending direction of metal–organic
polyhedra (MOPs) and the linker conformation to achieve MOFs with
framework isomerism. Six novel MOFs (CCNUF-1–6) based on an
octahedral MOP and different tritopic pyridine-based linkers were
successfully synthesized, among which the structural diversity increased
with increasing linker flexibility. The topologies (sql, kgd, and rtl) of these materials are
unprecedented in MOP-based MOFs. Moreover, highly porous CCNUF-2–6
showed remarkable iodine uptake capacities in the range of 2.51 to
3.11 g g–1. This study emphasizes the potential
of MOPs containing open metal sites as versatile platforms for the
development of diversified hierarchically porous MOFs with enhanced
functional properties.