Flexible side arms of ditopic linker as effective tools to boost proton conductivity of Ni8-pyrazolate metal-organic framework

Ni(II)-Pyrazolate Framework Bearing a Metalated Schiff-Base Moiety for Electrocatalytic Hydrogen Evolution

“…Following the reported synthetic protocol, 43 a green, crystalline powder of NiL1 (see Figure 2a for the appearance of the as-made sample of NiL1) was prepared from a Boc 2 L1 molecule (Figure 1a) and Ni(OAc) 2 •4H 2 O (e.g., with Boc 2 L1/ Ni ratio = 1:2) solvothermally, using N,N-dimethylacetamide (DMA) and H 2 O as a mixed solvent (1:4, v/v) (note: water assists deprotection of the tert-butoxycarbonyl, Boc, group). 27 Employment of the Boc group is based on the following reasons: 43 To examine the possibility of coupling between the salicylaldehyde and amine group, a model Schiff-base reaction was carried out at the molecular level. 1 H and 13 C NMR spectra of Boc 2 L1-Sal (see Figures S7 and S8) along with a strong signal at 1612 cm −1 of C�N stretching in its Fourier transform infrared (FTIR) spectrum (Figure S11) tell that the target Schiff-base molecules can be prepared successfully.…”

“…Following the reported synthetic protocol, a green, crystalline powder of Ni L1 (see Figure a for the appearance of the as-made sample of Ni L1 ) was prepared from a Boc 2 L1 molecule (Figure a) and Ni(OAc) 2 ·4H 2 O (e.g., with Boc 2 L1 /Ni ratio = 1:2) solvothermally, using N,N -dimethylacetamide (DMA) and H 2 O as a mixed solvent (1:4, v/v) (note: water assists deprotection of the tert -butoxycarbonyl, Boc, group) . Employment of the Boc group is based on the following reasons: (1) the Boc group is well known to mask the pyrazole donors and hence minimize their interference with the transition metal catalyst during the Sonogashira coupling reaction, (2) the solubilizing Boc group makes linker purification easier, and (3) its in situ deprotection during the solvothermal reaction promotes the crystallinity of the resultant MOF.…”

“…The stability of molecular electrocatalysts can be extended by sterically bulky ligand templates, yet along with the sacrifice of catalytic activity . Metal–organic frameworks (MOFs), composed of metal-ion/cluster nodes and organic linkers, represent a promising class of functional crystalline porous materials applied to various areas such as gas separation, sensing, catalysis, and drug delivery − due to their high specific surface area, tunable pores, rich topology, etc. − MOF is an ideal platform for a tailor-made heterogeneous catalyst as metal-centered active sites are well dispersed over the whole framework. Benefiting from the high surface area and porosity, additional active sites can be installed inside the framework through post-synthetic modification, PSM, to further enhance the catalytic activity of the MOFs.…”

Removing Perfluoro Pollutants PFOA and PFOS by Two-Pronged Design of a Ni8-Pyrazolate Porous Framework

“…The alkaline function merits extra attention as MOFs (especially carboxylate ones) are especially sensitive to and incompatible with alkaline conditions (due to facile hydrolysis of the metal node). For this, we choose the 3D Ni 8 -pyrazolate network as the scaffold as softer Ni–N links therein provides for more alkaline stability (e.g., even at pH = 14). − This framework system is also less prone to partial collapse upon activation as is the case for many Zr–carboxylate systems. − Recently, linker deficiency has been discovered in this MOF system, − offering open metal sites for anchoring additional alkaline ligands for functionalization.…”

Design and facile synthesis of a photothermally active metal–organic framework bearing persistent radicalsviapost-synthetic thermal annealing

“…Metal–organic framework (MOF) materials are porous crystalline materials assembled from metal ions/clusters and organic ligands through the formation of a coordination network. 15 Owing to the high crystallinity and well-defined structures, MOFs have been widely applied in gas separation, 16,17 catalysis, 18,19 ratiometric luminescent sensing, 20,21 proton conductivity, 22,23 etc. Recently, there arose reports on radicals stabilized within MOFs through isolation of radicals from quenching species outside the framework and dispersal of radicals over the whole framework.…”