Publications by authors named "Zhengkai Cao"

A thorium-carbon double bond that corresponds to the sum of theoretical covalent double bond radii has long been sought after in the study of actinide-ligand multiple bonding as a synthetic target. However, the stabilization of this chemical bond remains a great challenge to date, in part because of a relatively poor energetic matching between 5f-/6d- orbitals of thorium and the 2s-/2p- frontier orbitals of carbon. Herein, we report the successful synthesis of a thorium-carbon double bond in a carbon-bridged actinide-transition metal cluster, i.

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Article Synopsis
  • Endohedral fullerenes are molecules that can encapsulate metal clusters, and this study introduces a new type called fluoride clusterfullerenes (FCFs).
  • The researchers successfully synthesized FCFs using various actinides, rare earth metals, and alkaline earth metals without needing extra modifications, revealing that adding a fluorine atom alters the metal-metal bonding significantly.
  • Their findings indicate that compounds like ThF@(7)-C and CaScF@(6)-C exhibit unique bonding interactions and promising magnetic properties, showcasing the potential of FCFs in future applications.
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Metal-metal bonding is crucial in chemistry for advancing our understanding of the fundamental aspects of chemical bonds. Metal-metal bonds based on alkaline-earth (Ae) elements, especially the heavier Ae elements (Ca, Sr, and Ba), are rarely reported due to their high electropositivity. Herein, we report two heteronuclear di-EMFs CaY@(6)-C and CaY@(5)-C, which contain unprecedented single-electron Ca-Y metal-metal bonds.

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Hydrodenitrogenation (HDN) experiments and density functional theory (DFT) calculations were combined herein to study the substituent effects of the nitrogen heterocycle on the HDN behaviors of indole and quinoline. Indole (IND), 2-methyl-indole (2-M-IND), 3-methyl-indole (3-M-IND), quinoline (QL), 2-methyl-quinoline (2-M-QL) and 3-methyl-quinoline (3-M-QL) were used as the HDN reactant on the NiMo/γ-AlO catalyst. Some key elementary reactions in the HDN process of these nitrogen compounds on the Ni-Mo-S active nanocluster were calculated.

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A long-time evaluation of -butane oxidation over an industrial vanadium-phosphorus-oxygen (VPO) catalyst was implemented. The catalytic performances for -butane oxidation during this period were obtained. It was shown that the conversion of -butane increased with the evaluation time, but the selectivity of the maleic anhydride (MA) product decreased gradually.

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Advanced microwave absorption (MA) materials have attracted widespread attention to meet the challenges of electromagnetic (EM) pollution. Herein, MgFeO/MgO/C fibers were successfully prepared via electrospinning technology and carbonization, and their surfaces were coated by MoS via hydrothermal method. The EM wave absorption performance of composites was enhanced due to the introduction of MoS.

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