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Recently, theoretical calculations have played an irreplaceable role in the discovery of electrocatalysts as a relatively time‐efficient, cost‐effective, and predictable method. More importantly, theoretical calculations can help screen out the best active reaction sites and modulate them accordingly, which is beneficial for the development of efficient catalysts. In this concept, we focus on the important role of theoretical calculations in determining catalytic active sites and understanding reaction mechanisms, emphasizing its importance in assisting the design and synthesis of efficient oxygen reduction reaction catalysts. Finally, we provide an outlook on the challenges and future development trend in this field. [ABSTRACT FROM AUTHOR]

Abstract A new superhydrophobic surface based on multi-scales nanoparticle was designed and prepared to enhance the robustness and reproducibility. The influence of multi-scale nanoparticles on the structure and property of [...]

Oxides supported precious metals have wide applications in (electro‐)catalysis. Although single atom dispersion is known as the most efficient metal utilization strategy, the dependence of the catalytic activity on different sites consisted of various anchoring sites for single atoms is largely unknown. Here, the electrocatalytic activities of crystalline α‐MnO2 with atomistic Pd locating at different sites including substitutional, tunnel, and surface‐bound sites are first predicted, and then experimentally validated by applying different synthetic methods including hydrothermal reaction and impregnation‐calcination. The quantum chemistry calculations together with experimental characterization suggest that substitutional Pd/MnO2 possesses higher activity than the other samples due to the favorable geometric and electronic structures. Substitutional Pd can work synergistically with vicinal Mn sites toward cleavage of OO bonds. This work provides a comprehensive understanding on the impact of atomistic anchoring site and advances the reliable control over the electrocatalytic performance of oxide‐supported single atoms. [ABSTRACT FROM AUTHOR]

The Fe3O4/PANI rod/rGO nanocomposites were prepared by a new synthesis process, and their microwave absorbing properties were further evaluated. Taking advantage of the synergistic effects of the different components in the nanocomposites and the merits of the proposed synthesis strategies, the Fe3O4/PANI rod/rGO nanocomposites showed excellent microwave absorption performance, especially for obtaining giant absorption bandwidth (ca. 14.6 GHz, <− 10 dB). The work does not only confirm the formation of Fe3O4/PANI rod/rGO nanocomposites with wide absorption frequency range, strong absorption property and lightweight, but also provide a new synthesis process of electromagnetic wave absorbents for large-scale production. [ABSTRACT FROM AUTHOR]

Recently, bimetallic nanoparticles (NPs) are promising for driving nitrate (NO3 −) reduction reaction (NO3RR) to produce ammonia (NH3) due to their multiple active sites and electron redistribution via strong metal–metal interaction. However, the quantitatively determining the atomic configuration of the active sites and revealing their respective roles in NO3RR process are still challenged. Herein, the configuration of atomically ordered PdFe3 L12 intermetallic NPs into mesoporous carbon nanofibers (O‐PdFe3‐mCNFs) is reported as an efficient NO3RR catalyst for NH3 synthesis. Compared to the face‐centered cubic one, the O‐PdFe3‐mCNFs demonstrate a high NO3− removal of 98.3% within 270 min with a large NH3 yield rate of 1014.2 µmol h−1 cm−2. The detailed in situ and theoretical analysis reveals that the high performance of O‐PdFe3‐mCNFs is attributed to the synergetic effect from the periodic adjacent Pd‐Fe pair sites at the ordered (110) facet via accelerating proton relay, where the Fe sites show preferable stabilization of nitrogen−oxygen (*NO) intermediates while Pd sites serve as proton reservoir for *NO hydrogenation. Moreover, the strong d‐d orbital hybridization tunes d‐band center of the alloy NPs and effectively modulates the adsorption energy of *NO3− and *NO. This synergetic electrocatalyst design offers a new avenue for developing highly efficient multifunctional NO3RR catalysts. [ABSTRACT FROM AUTHOR]

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)-N 4 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-N 4 SAs act as a modulator to assist the O 2 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-N 4 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., (© 2023 Wiley-VCH GmbH.)

Here, we report a universal single-atom coating (SAC) strategy by taking advantage of the rich chemistry of tannic acid (TA). TA units not only self-assemble into a cross-linked porous polyphenolic framework, but also can grip on different substates via multiple binding modes. Benefiting from the diverse chelating ability of TA, a series of mono-, and bi-metallic SACs can be formed on substrates of different materials (e. g., carbon, SiO 2 , TiO 2 , MoS 2 ), dimensions (0D-3D) and sizes (50 nm-5 cm). By contrast, uniform SAC cannot be achieved using common approaches such as pyrolysis of metal-dopamine complexes or metal-organic frameworks. As a proof-of-concept demonstration, two Co SACs immobilized on graphene and TiO 2 were prepared. The former one shows six-fold higher mass activity than Pt/C toward oxygen reduction. The latter one displays outstanding photocatalytic activity owing to the high activity of the single atoms and the formation of the single-atom coating-TiO 2 heterojunction., (© 2022 Wiley-VCH GmbH.)