Nanocrystals of a zirconium-based metal-organic framework (Zr-MOF) were grown on carboxylate-functionalized carbon nanotubes (CNT) at room temperature to synthesize electrically conducting Zr-MOF-CNT nanocomposites. To further enable charge transport within the Zr-MOF phase via redox hopping under electrochemical conditions, redox-active manganese sites were then installed in the Zr-MOF and nanocomposites at room temperature by means of the solvothermal deposition in MOFs (SIM) technique. The redox hopping behav- [a]

In this study, a strategy that can result in the polyaniline (PANI) solely confined within the nanopores of a metal–organic framework (MOF) without forming obvious bulk PANI between MOF crystals is developed. A water‐stable zirconium‐based MOF, UiO‐66‐NH2, is selected as the MOF material. The polymerization of aniline is initiated in the acidic suspension of UiO‐66‐NH2 nanocrystals in the presence of excess poly(sodium 4‐styrenesulfonate) (PSS). Since the pore size of UiO‐66‐NH2 is too small to enable the insertion of the bulky PSS, the quick formation of pore‐confined solid PANI and the slower formation of well dispersed PANI:PSS occur within the MOF crystals and in the bulk solution, respectively. By taking advantage of the resulting homogeneous PANI:PSS polymer solution, the bulk PANI:PSS can be removed from the PANI/UiO‐66‐NH2 solid by successive washing the sample with fresh acidic solutions through centrifugation. As this is the first time reporting the PANI solely confined in the pores of a MOF, as a demonstration, the obtained PANI/UiO‐66‐NH2 composite material is applied as the electrode material for supercapacitors. The PANI/UiO‐66‐NH2 thin films exhibit a pseudocapacitive electrochemical characteristic, and their resulting electrochemical activity and charge‐storage capacities are remarkably higher than those of the bulk PANI thin films.

Silver nanoparticles (NPs) are installed into a porphyrinic zirconium-based metal−organic framework (Zr-MOF), NU-902, through a postsynthetic modification followed by an ion-exchange process. Both the framework-immobilized Ag(I) ions and partially reduced silver NPs confined within the nanopores of NU-902 with the size of around 3 nm are found in the obtained composite. As both the silver NPs and porphyrinic linkers of NU-902 are electrocatalysts for the oxidation of nitrite, the obtained nanocomposite can be applied for the electrochemical nitrite sensor, and the resulting sensing performance is significantly better than that of the pristine porphyrinic Zr-MOF.

Electrically conductive nanocomposites composed of a zirconium-based metal−organic framework (MOF) and nanocarbons are synthesized by in situ growth of MOF nanocrystals in the presence of graphene nanoribbons (GNRs) or graphene oxide (GO). The electrical conductivity and porosity of the obtained MOF-based nanocomposites are highly tunable by adjusting the MOF-to-carbon ratio as well as the type of nanocarbons used during the synthesis. Redox-active manganese sites are thereafter decorated in the MOF structure in these nanocomposites to render redox hopping in MOF under electrochemical conditions, and the pseudocapacitive behaviors of these MOF−GNR and MOF−GO nanocomposites are investigated in aqueous electrolytes. With the electrical conductivity provided by nanocarbons and the high-density redox-active manganese sites supported by the porous framework, the Mndecorated nanocomposites exhibit better performances as the materials for pseudocapacitors than the pristine Mn-decorated MOF and nanocarbons.

In this study, metallic molybdenum nanoparticles confined in the nanopores of a zirconium-based MOF (Zr-MOF), MOF-808, are prepared by a self-limiting decoration of spatially isolated Mo(VI) sites on the hexa-zirconium nodes of MOF-808, followed by the electrochemical reduction of Mo(VI) to metallic Mo. The obtained pore-confined Mo exhibits reversible redox activity in a neutral aqueous electrolyte and serves as the pseudocapacitive material for negative electrodes. By introducing another MOF-based pseudocapacitive material that can be used for positive electrodes, a manganese-decorated Zr-MOF-carbon nanotube nanocomposite, as a demonstration, all-Zr-MOF-based asymmetric pseudocapacitors with an aqueous electrolyte are fabricated.

A redox-active vanadium-based polyoxometalate, V10O28, was post-synthetically immobilized into a water-stable zirconium-based metal–organic framework, NU-902. The adsorbed V10O28 in NU-902 renders charge hopping in the framework in aqueous electrolytes, and...

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The cold rolled strip undergoes great transforming of micro-organization and change in properties in continuous annealing furnace. At the same time, it is acted upon by all kinds of forces, such as tensile and compressive stresses, bending stress, thermal stress. and thus it would affect stability of the steel strip. The finite element model of steel strip and guide rollers are established, and the ANSYS software is used to study the effects on transverse stress distribution under different strip shapes that contains center buckle, double edge wave, compound buckle, quarter buckle and quality shape. Profile of guide rollers such as different crowns and straight lengths are also be researched which is intended to provide a reliable base in theory for getting reasonable profile of guide rollers and homogenizing the tensile stress to improve shape quality.