Heterometallic Organic Frameworks Based On Schiff Base Ligands And Fe~Ⅲ/Cd~Ⅱ Ions:Structures,Adsorption Performance For Dyes And Photocatalytic Degradation Of 4-Chlorophenol

In this context,we synthesized three bi-metal heterometallic-organic frameworks（HMOFs）composed of dicarboxyl-functionalized Schiff base ligands and Fe（III）/Cd（II）ions by usingsolventthermalmethods.Threecompounds,[Cd₂（Fe-L1）₂（μ₂-O）（H₂O）₂]·4DMF·MeOH·2H₂O（1）(H₄L1=N,N’-cyclohexanediaminebis-（2-hydroxyl-6-carboxy-1-naphthaldehy）,[Cd₂（Fe-L2）₂（μ₂-O）（H₂O）₂]·3DMF（2）(H₄L2=N,N’-o-phenylene diaminebis-（2-hydroxyl-6-carboxy-1-naphthaldehy）and[Cd₂（Fe-L3）₂（μ₂-O）（H₂O）₂]·4H₂O（3）(H₄L3=N,N’-ethylenediaminebis-（2-hydroxyl-6-carboxy-1-naphthaldehy）were structurally characterized by single-crystal X-ray diffraction.In compounds 1 and 2,L1^4-and L2^4-anions exhibit the same of coordination fashions.Two pairs of Cd1 and Cd2 ions are bridged by carboxylates of L1^4-and L2^4-anions to form a[Cd₄（COO）₈（H₂O）₄]tetranuclear cluster.The tetranucler clusters are connected by L1^4-and L2^4-ligands to form a porous 3D framework.In compound 3,L3^4-anions has only one coordination mode and links with Cd（II）ions to form one-dimensional structure.Compounds 1 and 2 were characterized by powder X-ray diffractions,elemental analysis,infrared spectra（IR）and therogravimetric（TG）analysis.Organic dyes adsorption and photocatalytic degradation of the 4-chlorophenol under visible-light irradiation of compounds1 and 2 were also studied.