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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 strong electronic coupling of NiCo 2 O 4 and CeO 2 promotes the formation/decomposition of Li 2 CO 3. [Display omitted] • Strong electronic coupling effect could promote the formation of membrane-like Li 2 CO 3. • Experiments and DFT results confirmed the Li 2 CO 3 formation is through a surface-adsorption model. • NiCo 2 O 4 /CeO 2 cathode exhibits a good cyclability of 240 cycles at 2000 mA g−1. The sluggish CO 2 reduction/evolution kinetics at the cathode severely hamper the industrial applications of Li–CO 2 batteries, especially under large current densities. Herein, NiCo 2 O 4 /CeO 2 with a strong electron coupling effect is prepared via solvothermal method and calcination to realize the rapid kinetics of discharge and charge processes. The electronic character of the catalyst and the growth behavior of Li 2 CO 3 are investigated through density functional theory (DFT) and experiments, elucidating the reaction mechanism of Li–CO 2 battery. The results demonstrate that the strong electronic coupling of NiCo 2 O 4 and CeO 2 enhances the intrinsic activity of the catalyst and promotes the generation of membrane-like Li 2 CO 3 with good reversibility, thereby enhancing battery performance at a large current density. Consequently, NiCo 2 O 4 /CeO 2 achieved a large specific capacity of 7767 mAh g−1 under 2000 mA g−1 and could be stably cycled more than 240 times, outperforming most reported metal-based catalysts. This work underscores the important role of strong electronic coupling in facilitating the formation and decomposition of Li 2 CO 3 , providing valuable insight for designing cathode catalysts with high-rate properties for Li–CO 2 batteries. [ABSTRACT FROM AUTHOR]

The strong interaction on CuCo-V 2 O 3 heterointerface facilitates the modulation of local electron density, charge transfer and adsorption behavior, which promotes the activation of –OH/–CHO groups and the corresponding rate-determining step, thus enhancing the HMFOR activity. [Display omitted] • CuCo-V 2 O 3 heterostructure modulates charge region to activate groups of HMF. • Higher activation of hydroxymethyl group induces the RDS change to HMF → HMFCA. • High FDCA selectivity (99.11 %) and stability (40 cycles) for HMF oxidation. 5-Hydroxymethylfurfural electrooxidation reaction (HMFOR) has attracted increasing attention due to energy conservation and value-added production. It is crucial to design highly active catalysts with fast kinetics and reveal the catalytic mechanism. Herein, the activation of hydroxymethyl/aldehyde groups is tuned on V 2 O 3 -modificated CuCo for efficient HMFOR. Experimental and theoretical results reveal that strong electron transfer occurs on the heterointerface between V 2 O 3 and CuCo, endowing its unique electronic structure and conductivity. Meanwhile, CuCo-V 2 O 3 heterostructure facilitates the modulation of local electron density, charge transfer, and adsorption behavior to promote the activation of hydroxymethyl/aldehyde groups. The higher activation of hydroxymethyl groups than that of aldehyde groups over CuCo-V 2 O 3 induces an altered rate-determining step for HMFOR. Consequently, CuCo-V 2 O 3 presents enhanced HMFOR activity (E 10 , 1.27 V RHE), reaction kinetics (38 mV dec−1), 2,5-furandicarboxylic acid selectivity (99.1%), and stability (40 successive cycles). This work provides a strategy for designing highly active catalysts for synthesizing value-added products. [ABSTRACT FROM AUTHOR]

An amorphous-crystalline heterostructure (Ni/NiMoO 4 /NiCo(OH) x) is prepared by wet chemical etching method for HMFOR and HER. The interaction between NiCo(OH) x and Ni/NiMoO 4 heterointerface regulates the electronic structure of catalyst to facilitate the adsorption behavior of reaction intermediates, thereby showing good performance for HMFOR-assisted H 2 production. [Display omitted] • Coupling of crystalline and amorphous materials provides abundant active sites. • Interactions between heterointerfaces optimize the adsorption of intermediates. • High FDCA selectivity (99.8%) and stability (40 cycles) for HMF oxidation. • Only 1.34 V is required to reach 10 mA cm−2 for HMFOR-assisted H 2 production. The development of catalysts with high activity, selectivity, and stability is critical for biomass upgrading coupled with hydrogen evolution. In this study, we present a simple method for fabricating crystalline-amorphous phase heterostructures using the etching effect of the acidic medium generated during cobalt salt hydrolysis, resulting in the formation of NiCo(OH) x -modified Ni/NiMoO 4 nanosheets electrode (NiCo(OH) x /Ni/NiMoO 4 /NF). The nanosheets array formed during the synthesis process enlarges the surface area of the prepared catalyst, which facilitates the exposure of electrochemically active sites and improves mass transfer. Unexpectedly, the strong coupling interactions between the amorphous-crystalline heterointerface optimize the adsorption of reaction molecules and the corresponding charge transfer process, consequently boosting the catalytic activity for the 5-hydroxymethylfurfural oxidation reaction (HMFOR) and hydrogen evolution reaction (HER). Specifically, NiCo(OH) x /Ni/NiMoO 4 /NF catalyst requires only 1.34 V to obtain a current density of 10 mA cm−2 for HMFOR-coupled H 2 evolution, and operates stably for 13 consecutive cycles with good product selectivity. This work thus provides insights into the design of efficient and robust catalysts for HMFOR-assisted H 2 evolution. [ABSTRACT FROM AUTHOR]