Hierarchically Ordered Two-Dimensional Coordination Polymers Assembled from Redox-Active Dimolybdenum Clusters

Coordination polymers
(CPs) supporting tunable through-framework
conduction and responsive properties are of significant interest for
enabling a new generation of active devices. However, such architectures
are rare. We report a redox-active CP composed of two-dimensional
(2D) lattices of coordinatively bonded Mo2(INA)4 clusters (INA = isonicotinate). The 2D lattices are commensurately
stacked and their ordering topology can be synthetically tuned. The
material has a hierarchical pore structure (pore sizes distributed
between 7 and 33 Å) and exhibits unique CO2 adsorption
(nominally Type VI) for an isotherm collected at 195 K. Furthermore,
cyclic voltammetry and electrokinetic analyses identify a quasi-reversible
feature at E1/2 = −1.275 V versus
ferrocene/ferrocenium that can be ascribed to the [Mo2(INA)4]0/–1 redox couple, with an associated standard
heterogeneous electron transfer rate constant ks = 1.49 s–1. The tunable structure, porosity,
and redox activity of our material may render it a promising platform
for CPs with responsive properties.