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Two isostructural Co/Ni(II)-based coordination polymers, namely, {[Co1/2(bpba)(H2O)]⋅2H2O}n (1) and {[Ni1/2(bpba)(H2O)]⋅2H2O}n (2), where Hbpba = 3,5-bis (pyridin-4-ylmethoxy) is benzoic acid, were synthesized hydrothermally and characterized. The Hbpba ligand contains two flexible pyridines and one rigid benzoic acid group. Due to the free rotation of methoxy groups, pyridine groups in Hbpba can participate in the coordination of metal ions. Photocatalysis of compounds 1 and 2 on six dyes was studied and the results shown that compounds 1 and 2 had the best degradability to rhodamine B and methyl blue, respectively. [ABSTRACT FROM AUTHOR]

One luminescent Cd2+ coordination polymer, {[Cd(tbca)(H2O)]}n (1) (Htbca = 4'-(1H-tetrazol-5-yl)-biphenyl-4-carboxylic acid), has been synthesized and characterized by infrared spectroscopy and powder X-ray diffraction. Structural analysis revealed that 1 was a 3D framework with a 3,6-connected rtl topology. Fluorescence titration experiments demonstrated that 1 was an excellent multi-functional probe for metal ions and amino acids. [ABSTRACT FROM AUTHOR]

A new coordination polymer, {[Cd(BIPA)(1,3-bdc)](DMF)}, based on bis(4-(1H-imidazol-1- yl)phenyl)amine (BIPA) and 1,3-dicarboxybenzene (1,3-Hbdc) was synthesized and showing 2D → 3D structure via π-π* interaction of BIPA molecules in the nearby networks in the complex. Investigation of photophysical properties showed that the complex exhibits a strong emission in the range of 350-425 nm (λ = 375 nm upon excitation at 327 nm). [ABSTRACT FROM AUTHOR]

Chiral coordination polymers have attracted much attention due to their special properties and significant applications. In this work, we synthesized two non-centrosymmetric ligands, N,N-bis(4-(1H-imidazol-1-yl)phenyl)-4-(pyridin-4-yl)aniline (DIMPPA) and N-(4-(1H-imidazol-1-yl)phenyl)-4-(pyridin-4-yl)-N-(4-(pyridin-4-yl)phenyl)aniline (MIDPPA), via structural modification of two reported centrosymmetric ligands; after that achiral → chiral induction occurred in the construction of three coordination polymers namely {[Cd(DIMPPA)(5-OH-bdc)](H2O)}n (1), {[Co(DIMPPA)(5-OH-bdc)](H2O)}n (2) and {[Cd2(MIDPPA)2(d-ca)2(H2O)2](H2O)5}n (3), when replacing the reported centrosymmetric ligands with non-centrosymmetric ligands (5-OH-H2bdc = 5-hydroxyisophthalic acid, d-H2ca = d-camphoric acid). Isostructural complexes 1 and 2 exhibit chiral 2D → 3D frameworks with the coexistence of polyrotaxane and parallel polycatenation features. Complex 3 shows two-fold interpenetrating 3D chiral architecture with cds-type topology. The luminescence emissions of both complexes 1 and 3 are mostly assignable to the internal π→π* electron transition in DIMPPA and MIDPPA, respectively. Complex 3 can satisfy the fundamental requirement of second-order nonlinear optical materials. [ABSTRACT FROM AUTHOR]

Magnetic coordination polymers have attracted considerable interest due to their novel structures and potential applications. In this paper, one new 2D magnetic manganese coordination polymer {[Mn(bimb)(OBA)]} n ( 1 ) was synthesized under solvothermal conditions based on 4,4′-bis(1H-imidazol-1-yl-methyl)biphenyl (bimb) and 4,4′-oxybis(benzoate) (H 2 OBA). Complex 1 contains [Mn(CO 2 )] n 1D chains and magnetic susceptibility measurements indicate that compound 1 exhibits an antiferromagnetic coupling interaction. In addition, complex 1 exhibits solid-state photoluminescence and high thermal stability. [ABSTRACT FROM AUTHOR]

Entangled coordination polymers have attracted considerable interest due to their novel structures and potential applications. In this paper, one new 2D→3D porous zinc coordination polymer {[Zn2(DPDBT)2(OBA)2](H2O)3}n (1) with parallel polycatenation was synthesized under solvothermal conditions based on 2,8-di(pyridin-4-yl)dibenzo[b,d]thiophene (DPDBT) ligand. In addition, complex 1 exhibits interesting solid-state photoluminescence and high thermal stability. [ABSTRACT FROM AUTHOR]

Abstract: Flexible carboxylic ligands have attracted considerable interest due to their excellent stretchable capacity and coordinative ability. In this paper, one new 2D zinc coordination polymer {[Zn(tcpob)2/3(H2O)2/3]·(H2O)2/3}n with trinuclear zinc cluster units was prepared under hydrothermal conditions based on 1,3,5-tri(4-carboxyphenoxy)benzene ligand. In addition, the solid-state photoluminescent spectra were measured at room temperature. [Copyright &y& Elsevier]

The new complexes {[Co 2 (BPPA)(hfipbb) 2 (H 2 O)(DMF) 2 ](H 2 O) 4 } n and {[Ni 2 (BPPA)(hfipbb) 2 (H 2 O)(DMF) 2 ](H 2 O) 4 } n have been synthesized under solvothermal conditions. These isostructural complexes exhibit 2D bilayer networks with unprecedented {4 11 .6 4 } topology. [ABSTRACT FROM AUTHOR]

The new coordination polymer {[Co4(DPDBT)5(fuma)4(H2O)2](NO3)4(H2O)7} n , where DPDBT is 2,8-di(pyridin-4-yl)dibenzo[b,d]- thiophene and fuma is fumarate dianion, was prepared; X-ray diffraction analysis revealed that it exhibits a 2D gek2 network with the coexistence of trinuclear and uninuclear building units. [ABSTRACT FROM AUTHOR]

One zinc coordination polymer based on 5-(4-(tetrazol-5-yl) phenyl) m-phthalic acid (tpia) was synthesized. It was characterized by powder X-ray diffraction. Fluorescence titration experiments show that 1 is a multifunctional probe for metal ions and antibiotics. In addition, its electrocatalytic performance was improved and optimized by doping cobalt ions and pyrolysis, that is 1 -Co-700. 1 -Co-700 has a low initial potential (−423 ​mV), Tafel efficiency (101.9 ​mV·dec−1) and good cycle stability (stable after at least 1000 cycles). One new Zn-MOF was synthesized and could be as an excellent multifunctional probe for Fe3+, gatifloxacin and norfloxacin. Its HER performance was improved and optimized by doping cobalt ions. [Display omitted] • One new Zn-MOF was an excellent multifunctional probe. • It has a fluorescence quenching effect on Fe3+ in aqueous solution. • It has fluorescence quenching effects on antibiotics. • Its HER performance was improved and optimized by doping cobalt ions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two Zn-MOFs with no electrocatalytic activity were synthesized by one-pot method. • Simple Co2+ doping was used to improved electrocatalytic performance. • The mechanism was verified and the method was proved to be generalizable. • Two high-quality electrocatalysts with excellent cycle stability were obtained. • This work provides an idea to improve electrocatalytic performance. Hydrogen energy has been considering as an ideal renewable energy source and playing a very important role in daily life. Noble metal catalysts have shown excellent catalytic performance in electrolysis of water for hydrogen evolution, but their scarcity and high cost limit their large-scale use. Therefore, the design of non-noble metal catalysts with high catalytic activity and stability and low cost is an urgent problem to be solved. Two zinc-based coordination polymers have been synthesized by one-pot method. We developed an effective method through simple Co2+ doping, which improved and optimized the electrocatalytic performance to obtain two high-quality electrocatalysts for electrolysis of water to produce hydrogen with low starting potential (−210 mV and −240 mV), high Tafel efficiency (117.7 mV dec-1 and 127.8 mV dec-1) and excellent cycle stability (>95% LSV retention after at least 2000 cycles). We also synthesized two isomorphic Co-based or Ni-based coordination polymers, and found that their electrocatalytic performances were improved to some extent after the introduction of Co ions, but the effects were not as good as that of zinc-based coordination polymers. This work not only provides two examples of good electrocatalyst, but also provides an idea to improve and optimize the electrocatalytic performance. [ABSTRACT FROM AUTHOR]

At present, the shortage of energy is becoming more serious. As a new energy source, hydrogen energy is expected to solve the problem of energy shortage. We considered that doping sulfur may lead to better electrocatalytic hydrogen evolution (HER) performance of the coordination polymers. Therefore, we added sulfuric acid to adjust pH and expected to introduce sulfate ions into the structure during the synthesis. Finally, one cobalt-based coordination polymer (CP) was synthesized, namely {[Co 4 (bibp) 4 (SO 4 2−) 4 (H 2 O) 8 ]} n (1) (bibp ​= ​4,4′-bisimidazolylbiphenyl). As expected, this synergistic effect of cobalt, carbon and sulfur in the structure may enable compound 1 after calcination at high temperature to have better electrocatalytic hydrogen evolution performance. It has a low onset potential and Tafel slope of −137mV and 115 ​mV dec−1, respectively, and an overpotential of −252mV at a current density of 10 ​mA ​cm−2. And we also found that the material also has low resistivity and good stability with a good activity after 8 ​h of cycling. We selected a relatively simple organic ligand to construct a Co(II)-based coordination polymer. Sulfate ion was introduced during the synthesis process to improve the performance of hydrogen evolution by electrocatalysis. The LSV curve and Tafel curve show that compound 1 after calcination has a good application prospect with good cycling for HER in acidic media. [Display omitted] • Sulfuric acid was added to adjust pH and introduced into the structure. • The synergistic effect make 1 after pyrolysis have a good HER property. • It has a low onset potential and Tafel slope. • The HER performance of 1 -900 is relatively stable after 8 ​h of cycling. [ABSTRACT FROM AUTHOR]

A cluster-based multifunctional coordination polymer with a dual loop pseudo-rotaxane motif has been synthesized. The trinuclear Co 3 cluster and the ligand with a π-electron rich system jointly endow compound 1 with magnetism, dye degration and electrochemical properties. • Rotaxanes. • Crystal structure. • Magnetism. • Dye degradation. • Electrochemical capacitor. A trinuclear cobalt-based multifunctional coordination polymer with a dual loop pseudo-rotaxane motif, namely [Co 3 (DPFE‧H+) 2 (sdba2−) 4 (OH−) 2 (DPFE‧2H+)(CH 3 CN) (1), has been synthesized by a mixed ligand strategy under hydrothermal conditions (DPFE = 2,7-di(pyridin-4-yl)-9H-fluorene, H 2 sdba = 4,4′-sulfonyldibenzoic acid). Compound 1 has 1D + zero-dimensional (0D) → 1D armed pseudo-polyrotaxane character, in which the 1D dual ring chain [Co 3 (COO−) 4 (OH−) 2 (sdba2−) 4 is threaded by doubly protonated free DPFE ligands. The trinuclear cobalt cluster and π-electron rich system involving the ligands jointly endow compound 1 with magnetism, photocatalytic and electrochemical properties. Magnetic property measurements of 1 indicate that there exists weak antiferromagnetic coupling in the trinuclear [Co 3 (COO−) 4 (OH−) 2 unit, the experiments of photocatalytic degradation of dyes demonstrated that 1 has good catalytic activity for the degradation of methylene blue (MB) and the electrochemical results show that compound 1 exhibits a specific capacitance of 52.25 F g−1 at a current density of 1 A g−1 and retains 93.75% specific capacitance after 960 cycles. [ABSTRACT FROM AUTHOR]