Functional group induced structural diversities and photocatalytic, magnetic and luminescence sensing properties of four cobalt() coordination polymers based on 1,3,5-tris(2-methylimidazol-1-yl)benzene

• Published in: CrystEngComm 2020, Vol.22 (4), p.811-82
• Main Authors: Wang, Jun, Chen, Ning-Ning, Zhang, Chen, Jia, Li-Yong, Fan, Liming
• Format: Article
• Language: English
• Subjects: Aqueous solutions; Benzene; Bilayers; Cobalt; Coordination polymers; Crystallography; Functional groups; Hydrocarbons; Luminescence; Magnetic properties; Methylene blue; Photocatalysis; Photodegradation; Selectivity; Sulfur trioxide
• ISSN: 1466-8033; 1466-8033
• DOI: 10.1039/c9ce01474h

Based on the designed tripodal linker 1,3,5-tris(2-methylimidazol-1-yl)benzene (timb), four cobalt( ii ) coordination polymers, {[Co 4 (timb) 2 (Br-IPA) 4 ]·5H 2 O} n ( 1 ), {[Co(timb) 0.5 (NH 2 -IPA)]·4H 2 O} n ( 2 ), {[Co 5 (timb) 4 (OH-IPA) 4 ]·2NO 3 ·2DMA·2H 2 O} n ( 3 ), and {[Co 3 (timb) 2 (SO 3 -IPA) 2 (H 2 O) 2 ]·8H 2 O} n ( 4 ), have been obtained by adjusting the meta -functional groups of isophthalic acid (H 2 IPA). CP 1 displays an unprecedented 3D 3-nodal (3,4,8)-connected net with the point (Schlafli) symbol {4 2 ·6 4 }{4 2 ·6} 2 {4 6 ·6 14 ·7 4 ·8 3 ·9} based on trinuclear {Co 3 (COO) 6 } SBUs. CP 2 shows an interesting 2D (3,4)-connected {6 3 }{6 6 } bilayer with ABAB packing. CP 3 is a 2D 6-nodal (3,3,3,4,4,4)-connected sheet with the point (Schlafli) symbol {4·5 2 }{4·5 3 ·7 2 } 2 {4 2 ·5 2 ·6·7} 3 {4 3 }{5 3 } 2 . CP 4 exhibits a 2D + 2D → 3D interpenetrating net based on the 2D (3,4)-connected {6 3 }{6 6 } bilayer structure. CPs 1-4 possess excellent luminescence sensing properties for Fe 3+ and Cr 2 O 7 2− ions in aqueous solution with high sensitivity and selectivity. Besides, the magnetic properties as well as the photocatalytic activities for the degradation of methylene blue (MB) of CPs 1-4 under visible light have been investigated. Based on the designed tripodal linker timb, four cobalt( ii ) coordination polymers, {[Co 4 (timb) 2 (Br-IPA) 4 ]·5H 2 O} n ( 1 ), {[Co(timb) 0.5 (NH 2 -IPA)]·4H 2 O} n ( 2 ), {[Co 5 (timb) 4 (OH-IPA) 4 ]·2NO 3 ·2DMA·2H 2 O} n ( 3 ), and {[Co 3 (timb) 2 (SO 3 -IPA) 2 (H 2 O) 2 ]·8H 2 O} n ( 4 ), have been obtained.