The robust, high-valent Ni complex [(Py) Ni F (CF ) ] (Py=pyridine) was synthesized and fully characterized by NMR spectroscopy, X-ray diffraction, and elemental analysis. It reacts with aromatic compounds at 25 °C to form the corresponding benzotrifluorides in nearly quantitative yield. The monomeric and dimeric Ni CF complexes 2⋅Py and 2 were identified as key intermediates, and their structures were unambiguously determined by EPR spectroscopy and X-ray diffraction. Preliminary kinetic studies in combination with the isolation of reaction intermediates confirmed that the C-H bond-breaking/C-CF bond-forming sequence can occur both at Ni CF and Ni CF centers.
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http://dx.doi.org/10.1002/anie.201706237 | DOI Listing |
Nanoscale Horiz
January 2025
Research & Development Institute of Northwestern Polytechnical University in Shenzhen, Shenzhen, 518057, China.
Over-oxidation of surface ruthenium active sites of RuO-based electrocatalysts leads to the formation of soluble high-valent Ru species and subsequent structural collapse of electrocatalysts, which results in their low stability for the acidic oxygen evolution reaction (OER). Herein, a binary RuO/NbO electrocatalyst with abundant and intimate interfaces has been rationally designed and synthesized to enhance its OER activity in acidic electrolyte, delivering a low overpotential of 179 mV at 10 mA cm, a small Tafel slope of 73 mV dec, and a stabilized catalytic durability over a period of 750 h. Extensive experiments have demonstrated that the spillover of active oxygen intermediates from RuO to NbO and the subsequent participation of lattice oxygen of NbO instead of RuO for the acidic OER suppressed the over-oxidation of surface ruthenium species and thereby improved the catalytic stability of the binary electrocatalysts.
View Article and Find Full Text PDFAdv Sci (Weinh)
December 2024
School of Life Sciences, Northwestern Polytechnical University, 127 Youyi Road, Xi'an, 710072, China.
Developing novel cold-adapted nanozymes and elucidating their mechanisms of action remains a great challenge. Inspired by natural oxidases that utilize high-spin and high-valent metal-oxygen intermediates to achieve high efficiency at low temperatures, in this study, a series of MnO nanomaterials with varied valence and spin states are synthesized. The activity assay revealed that the oxygen vacancy-engineered ε-MnO nanozyme displayed excellent cold-adapted oxidase-like properties, and no observable activity loss is observed in the temperature range of -20 to 45 °C.
View Article and Find Full Text PDFJ Colloid Interface Sci
February 2025
College of Materials Science and Engineering, Institute for Graphene Applied Technology Innovation, Qingdao University, Qingdao 266071, China; College of Materials Science and Engineering, Linyi University, Linyi 276000 Shandong, China. Electronic address:
To replace precious metals and reduce production costs for large-scale hydrogen production, developing stable, high-performance transition metal electrocatalysts that can be used in a wide range of environments is desirable yet challenging. Herein, a self-supported hybrid catalyst (NiFeCrS/NF) with high electrocatalytic activity was designed and constructed using conductive nickel foam as a substrate via manipulation of the cation doping ratio of transition metal compounds. Due to the strong coupling synergy between the metal sulfides NiS, FeS, and CrS, as well as their interaction with the conductive nickel foam (NF), the energy barrier for catalytic reactions is reduced, and the charge transfer rate is enhanced.
View Article and Find Full Text PDFJ Am Chem Soc
December 2024
School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao, Shandong 266580, P. R. China.
Current research on emergent membrane materials with ordered and stable nanoporous structures often overlooks the vital facet of manufacturing scalability. We propose the preprocessed monomer interfacial polymerization (PMIP) strategy for the scalable fabrication of high-valent cluster-based metal-organic framework (MOF) membranes with robust structures. Using a roll-to-roll device on commercial polymer supports, Zr-fum-MOF membranes are continuously processed at room temperature through the PMIP approach.
View Article and Find Full Text PDFSmall
November 2024
State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong, 250353, P. R. China.
Highly-efficient and cost-effective electrocatalysts toward the oxygen evolution reaction (OER) are crucial for advancing sustainable energy technologies. Herein, a novel approach leveraging corrosion engineering is presented to facilitate the in situ growth of amorphous cobalt-iron hydroxides on nickel-iron foam (CoFe(OH)-m/NFF) within a NaCl-CoCl aqueous solution. By adjusting the concentration of the solution, the compositions can tailored and morphologies of these hydroxides to optimize the OER electrocatalytic performance.
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