In summary, cyano-ferrate complexes can be grafted to the eight-connected, hexa-zirconium(IV)oxy nodes of NU-1000, with an average loading of 1.1 iron per node and with retention of MOF crystallinity and mesoporosity. Single-crystal X-ray diffraction experiments indicate that the cyano-ferrate is sited in the MOF's small c-pore and that it attaches via loss of cyanide ligands and recruitment of either two or three oxy ligands of the node, i.e. it attaches in two forms, tentatively formulated as Fe(II)(CN)4(-OH)2 4-and Fe(II)(CN)3(-OH)2(-O) , where  refers to bridging between iron and zirconium (and for -O, bridging also between three Zr(IV) ions). The UV-vis reflectance spectrum of FeCN@NU-1000 displays a broad feature that peaks at high energy and is speculatively ascribed to Fe-to-Zr charge transfer. With electrode-supported thin films (spincoat films), ~2% of the installed cyano ferrate complexes are electrochemically addressable on the tens of seconds time-scale reflecting the insulating nature of the nodes. Boosting the percentage of readily accessible (i.e., short-time accessible) electroactive iron centers likely will require devising a means of increasing the loading of cyano-ferrate species and thereby decreasing the separation distance (redox-hopping distance) between iron centers.