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The meticulous design of heterogeneous interfaces presents a promising approach for enhancing the electrocatalytic activity of Cu-based materials in nitrate reduction reactions. Herein, we developed a self-templated metal–organic frameworks transformation strategy to synthesize hollow multi-metallic oxide materials with well-defined interfaces. By utilizing novel hollow Cu–Co bimetallic Prussian blue analogs as precursors, a hollow cage composed of ultra-small CuO/Co3O4 hetero-nanograins was successfully constructed. It was discovered that this structure greatly enhanced the electrocatalytic activity for the conversion of NO3− to NH3, achieving a remarkably high Faradaic efficiency (FE) for NH3 (with a maximum FE of 90.68%) at low overpotential ranges. Furthermore, electrochemical experiments and in situ spectroscopy provided evidence that electrochemically induced reconstruction led to the formation of synergistic sites between Cu and Co3O4. This enabled the sequential reduction of nitrate and nitrite on adjacent metal/metal oxide phases, resulting in the rapid generation of NH3. [ABSTRACT FROM AUTHOR]

In the present work, the three dimensional (3D) hydroelasticity characteristics of imperfect lattice sandwich panel (ILSP) subjected to water entry via analytical prediction and numerical simulations are proposed. Firstly, numerical investigations are performed on water entry characteristics based on Arbitrary Eulerian-Lagrange (ALE) coupling method for modeling fluid-structure interaction (FSI) at an impact velocity of 5.0m/s. The results show the impact pressure on total FSI surface of ILSP is generally lower than that of the perfect lattice sandwich panel. Then a novel semi-analytical method to calculate the elastic constants of ILSP is introduced. Based on this approach, an engineering computational model is developed to predict the deformation of ILSP, in which the total deformation is separated into two parts; local field deformation and global field deformation. Good agreement between the numerical and analytical results is achieved. And the effects of geometric parameters such as the thickness of face sheet, height of ILSP and relative density of core are discussed.

Tuning metal–support interactions (MSIs) to precisely control the selectivity of supported Cu catalysts toward the CO2 reduction reaction (CO2RR) is a crucial yet challenging topic. Herein, a series of CuO nanosheet/CeO2 nanorod composites with various morphologies and compositions were synthesized and used as electrocatalysts. The CO2RR product distributions of composites are experimentally verified to be dependent on the loading amounts and sizes of CuO nanosheets, with the maximum Faradaic efficiency (FE) of CH4 and C2H4 reaching 37.8 and 44.8%, respectively. The mechanism investigation supports our perspective that modulating the strength of the MSIs between CuO nanosheets and CeO2 nanorods not only influences the adsorption properties of CO2RR intermediates but also further dominates the formation of exposed facets during the CuO structural reconstruction process, thus customizing the CO2RR pathway. [ABSTRACT FROM AUTHOR]

Five molecular complexes with different non-noble metal centers were synthesized. The Co-based complex displays the highest photocatalytic performance for CO2 to CO conversion in aqueous media. It achieves high activity (TON = 41 017 and TOF = 3.80 s−1) and selectivity (87%) for the production of CO. [ABSTRACT FROM AUTHOR]

Developing high‐performance non‐noble‐metal electrocatalysts for the hydrogen evolution reaction (HER), which can be stably operated under various conditions is highly required in realistic production. In this work, a hierarchical architecture consisting of MoS2 and Co9S8 anchored on a reduced graphene oxide (rGO) substrate was first synthesized, then by introducing blank graphene oxide (GO) and multi‐walled carbon nanotubes (CNTs), interconnected three‐dimensional (3D) composite aerogels with high conductivity were obtained, showing a high activity for the HER, with low overpotentials (η10) at about 90 mV (0.5 M H2SO4), 176 mV (1.0 M PBS), and 102 mV (1.0 M KOH). The high performance might be caused by special hierarchical 3D structures maximally exposing the active edges of both MoS2 and Co9S8. Additionally, 3D MoS2/Co9S8/rGO‐CNTs showed a superior stability and could work stably under different conditions for more than 20 h or 1000 cycles, which is attributed to the good crystallinity after annealing, the highly symmetrical structures between Co9S8 and MoS2, and robust protection provided by the 3D carbon substrate. The results presented herein may provide an effective way to develop non‐noble‐metal electrocatalysts for different fields including the HER. A three‐dimensional composite is synthesized by a simple two‐step method and applied as a highly active pH‐universal electrocatalyst for the hydrogen evolution reaction. The material is stable in acid, neutral, and alkaline media. [ABSTRACT FROM AUTHOR]