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The atom‐cluster interaction has recently been exploited as an effective way to increase the performance of metal‐nitrogen‐carbon catalysts for oxygen reduction reaction (ORR). However, the rational design of such catalysts and understanding their structure‐property correlations remain a great challenge. Herein, we demonstrate that the introduction of adjacent metal (M)−N4 single atoms (SAs) could significantly improve the ORR performance of a well‐screened Fe atomic cluster (AC) catalyst by combining density functional theory (DFT) calculations and experimental analysis. The DFT studies suggest that the Cu−N4 SAs act as a modulator to assist the O2 adsorption and cleavage of O−O bond on the Fe AC active center, as well as optimize the release of OH* intermediates to accelerate the whole ORR kinetic. The depositing of Fe AC with Cu−N4 SAs on nitrogen doped mesoporous carbon nanosheet are then constructed through a universal interfacial monomicelles assembly strategy. Consistent with theoretical predictions, the resultant catalyst exhibits an outstanding ORR performance with a half‐wave potential of 0.92 eV in alkali and 0.80 eV in acid, as well as a high power density of 214.8 mW cm−2 in zinc air battery. This work provides a novel strategy for precisely tuning the atomically dispersed poly‐metallic centers for electrocatalysis. [ABSTRACT FROM AUTHOR]

The manipulation of polymeric micelles across extended-length scales is a key challenge in the design of integrated mesoporous materials with well-defined geometry and advanced functions. Herein, we demonstrate a modular assembly strategy to construct metal nanoparticle functionalized mesoporous carbon two-dimensional (2D) nanosheets by organizing zero-dimensional (0D) spherical monomicelle modules on the 2D supporting blocks. The modular assembly process involves two key steps: the "modularization" step is used to synthesize highly uniform metal–catecholamine (MC) complex functionalized monomicelle "modules" that can be conveniently assembled on the 2D supporting blocks (graphene oxide (GO), WS2, and MXene) in the following "assembly" step. After an annealing process, the resultant composites possess a single-layered 2D nanosheet surrounded by two single-layered mesoporous carbon at both sides and exhibit highly ordered mesostructures with large surface areas (~385 m2 g−1), tunable pore sizes (16–25 nm) and highly dispersed metal-containing nanoparticles. Due to the modularity of this assembly process, a range of metal species (Co, Fe, Ni, V, Cu, Pd, FeCo, CoNi, and FeCoNi) can be in-situ incorporated into the 2D mesoporous frameworks, which are partially embedded in the pore walls with the remaining part exposed in the pore channels. Benefiting from the unique textual structures, the resultant GO-derived functional mesoporous carbon nanosheets (Co as the functional species and being annealed at 850 °C) exhibit excellent electrocatalytic activity, long-term stability, and superior methanol tolerance for oxygen reduction reaction, which holds great potential as a catalyst for fuel cells. A modular assembly strategy has been demonstrated to construct metal nanoparticles functionalized mesoporous carbon two-dimensional (2D) nanosheets by organizing zero-dimensional (0D) spherical monomicelle modules on the 2D supporting blocks. The resultant materials exhibit an excellent electrocatalytic activity for oxygen reduction reaction, which holds a great potential as a catalyst for fuel cells. [ABSTRACT FROM AUTHOR]

Abstract: Two functionalized copper(II) and oxovanadium(IV) Schiff base complexes of type [M(N2O2), M=Cu, VO] bearing chloromethyl groups were respectively synthesized, directly anchored onto amino-modified SBA-15 materials and examined as catalysts for styrene oxidation. The purity of each ligand was confirmed by 1H NMR, FT-IR and elemental analysis. XRD, N2 adsorption/desorption and TEM results indicated that the mesoporous structure of SBA-15 remained intact throughout the grafting procedure. FT-IR, UV–vis spectroscopy plus TG–DTA data demonstrated the incorporation of copper(II) and oxovanadium(IV) complexes on amino-modified SBA-15. ICP-AES, SEM-EDX combined with XPS data further showed the different anchorage status of copper(II) and oxovanadium(IV) species on amino-modified SBA-15. The copper(II) Schiff base complex was anchored through the coordination of copper atom with the nitrogen atom of the amino group modified on the SBA-15 external surface. The oxovanadium(IV) Schiff base complex, however, was covalently anchored on SBA-15 via the condensation reaction of the chloromethyl group of the Schiff base with the amino group from the modified SBA-15 matrix. The catalytic properties of supported copper(II) and oxovanadium(IV) complexes in the oxidation of styrene with air or H2O2 as oxidant were investigated and compared with the properties of their homogeneous analogues. It was found that both heterogeneous copper(II) and oxovanadium(IV) catalysts were more active than their homogeneous analogues and that the product selectivity varied in cases of different oxidants. The supported oxovanadium(IV) complex showed high yield of styrene oxide (56.0%) and good recoverability when using air as oxidant. [Copyright &y& Elsevier]