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Construction of efficient catalysts to couple biomass upgrading with hydrogen production is significant for improving energy efficiency, which remains a challenge. Herein, a general method for manufacturing 3D hierarchical micro‐nano arrays consisting of template framework and nanoparticle‐decorated nanosheets is reported. This strategy provides an opportunity to controllably tailor the interfacial assembly of nanosheets on precursor template materials. The obtained Co@NiMoO‐Ni/NF exhibits enhanced electrocatalytic performance for biomass oxidation and hydrogen production. It only needs 1.21 V to achieve 10 mA cm−2 for 5‐hydroxymethylfurfural electrooxidation reaction (HMFOR) assisted H2 evolution reaction (HER). The good catalytic performance is ascribed to the intense interaction between template (Co) and nanoparticle‐decorated nanosheets (NiMoO‐Ni), which tunes the electron structure of the catalyst to optimize the adsorption behavior of HMFOR/HER intermediates and promote the bonds breakage of key intermediates in the HMFOR/HER process. This work thus provides a strategy for designing ideal catalysts for biomass upgrading‐coupled H2 production. [ABSTRACT FROM AUTHOR]

Developing efficient electrooxidation 5‐hydroxymethylfurfural (HMF) catalysts with high selectivity and fast reaction kinetic is challenging. The HMF oxidation reaction (HMFOR) involves the adsorption of HMF and OH− on the catalyst, thus understanding the adsorption behavior between the catalyst surface and reactants is vital. In this work, by studying the relationship between HMFOR performance and the adsorption behavior of reactants on different transition metal oxides (TMOs), it is discovered that the catalytic performance of TMOs is related to the adsorption capacity of OH− and HMF simultaneously. Subsequently, TMOs with different HMF and OH− adsorption abilities are coupled to further optimize the catalytic performance of HMFOR. Experimental and theoretical calculation results indicate that the electronic interactions between different TMOs can regulate the substrate adsorption behavior and electron transfer ability of the catalysts, which is beneficial for HMFOR. Among them, due to the strong interaction between the three components optimizes the adsorption capacity for HMF and OH−, NiO/CuO/Co3O4 exhibits the best HMFOR performance with FDCA selectivity of 99.6 % and formation rate of 16.45 mmol gcat−1 h−1. This work provides a design principle for HMFOR catalysts by modulating the adsorption behavior of reaction molecules. [ABSTRACT FROM AUTHOR]

The limited lifespan of aqueous Zn-ion batteries (ZIBs) is primarily attributed to the irreversible issues associated with the Zn anode, including dendrite growth, hydrogen evolution, and side reactions. Herein, a 3D Zn anode exposing Zn(002) crystal planes (3D-Zn(002) anode) is first constructed by an electrostripping method in KNO 3 solution. Experiments and theoretical calculations indicate that the priority adsorption of KNO 3 on Zn(100) and Zn(101) planes decreases the dissolution energy of Zn atoms, thereby exposing more Zn(002) planes. The 3D-Zn(002) anode effectively regulates ion flux to realize the uniform nucleation of Zn 2+ . Moreover, it can inhibit water-induced formation of side-products and hydrogen evolution reaction. Consequently, the 3D-Zn(002) symmetrical cell exhibits an exceptionally long lifespan surpassing 6000 h at 5.0 mA cm -2 with a capacity of 1.0 mAh cm -2 , and enduring 8500 cycles at 30 mA cm -2 with a capacity of 1.0 mAh cm -2 . Besides, when NH 4 V 4 O 10 is used as the cathode, the 3D-Zn(002)//NH 4 V 4 O 10 full cell shows stable cycling performance with a capacity retention rate of 75.7% after 4000 cycles at 5.0 A g -1 . This study proposes a feasible method employing a 3D-Zn(002) anode for enhancing the cycling durability of ZIBs., (© 2024 Wiley‐VCH GmbH.)

Developing catalysts with suitable adsorption energy for oxygen-containing intermediates and elucidating their internal structure-performance relationships are essential for the commercialization of Li-O 2 batteries (LOBs), especially under high current densities. Herein, NiCo 2 O 4 -CeO 2 heterostructure with a spontaneous built-in electric field (BIEF) is designed and utilized as a cathode catalyst for LOBs at high current density. The driving mechanism of electron pumping/accumulation at heterointerface is studied via experiments and density functional theory (DFT) calculations, elucidating the growth mechanism of discharge products. The results show that BIEF induced by work function difference optimizes the affinity for LiO 2 and promotes the formation of nano-flocculent Li 2 O 2 , thus improving LOBs performance at high current density. Specifically, NiCo 2 O 4 -CeO 2 cathode exhibits a large discharge capacity (9546 mAh g -1 at 4000 mA g -1 ) and high stability (>430 cycles at 4000 mA g -1 ), which are better than the majority of previously reported metal-based catalysts. This work provides a new method for tuning the nucleation and decomposition of Li 2 O 2 and inspires the design of ideal catalysts for LOBs to operate at high current density., (© 2024 Wiley‐VCH GmbH.)

Ammonia electrolysis is a promising technology to obtain green hydrogen with zero-carbon emission, in which ammonia oxidation reaction (AOR) and hydrogen evolution reaction (HER) occur at the anode and cathode, respectively. However, the lack of efficient catalysts hinders its practical application. Herein, PtZn alloy is combined with Nb 2 O 5 to construct a bifunctional heterostructure catalyst (PtZn-Nb 2 O 5 /C). The optimal sample with Nb 2 O 5 content of 7.05 wt % demonstrates the best performance with a peak current density of 304.1 mA mg -1 Pt for AOR, and it is only reduced by 17.0% after 4000 cycles of durability tests. For HER, it has a low overpotential of 34 mV at -10 mA cm -2 under the alkaline condition. This can be ascribed to the interfacial interaction between the PtZn alloy and Nb 2 O 5 , which adjusts the adsorption behavior of OH ad to concurrently promote AOR and HER activity. This work thus proposes a viable strategy to design an efficient bifunctional catalyst for hydrogen generation from ammonia electrolysis.