2D Co and Cd Coordination Polymers Assembled with Fumarate and 4,4′‐Trimethylenedipyridine: Syntheses, Crystal Structures, Magnetism, Luminescence and Catalytic Properties

Two novel coordination polymers, {[Co(H 2 O)(fum)(tmdp)]·2H 2 O} n ( 1 ) and {[Cd(H 2 O) (fum)(tmdp)]·H 2 O} n ( 2 ) (fum = fumarate, tmdp = 4,4′‐trimethylenedipyridine), were obtained by self‐assembly reactions at ambient conditions. These polymers have 2D arrays, both with a sql topology. Co(II) ions in 1 are hexa‐coordinated with a distorted octahedral geometry; meanwhile, Cd(II) ions in 2 are hepta‐coordinated with a distorted pentagonal bipyramid geometry. Polymer 1 possesses weak antiferromagnetic coupling with ⊖ (C–W) = −15.2 K from the Curie–Weiss model fitting. In the solid‐state, polymer 2 exhibits two photoluminescent emissions at 316 and 364 nm, upon excitation at 265 nm. Using Fenton‐like processes, under visible‐light, 1 can degrade 60% of Congo red (CR) dye in 20 min, while 2 has better efficiency with a 70% CR degradation at that same time. Moreover, both polymers accomplish coagulation of CR, 1 performs it without Fenton‐like conditions, while 2 does it with and without Fenton‐like conditions.