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Graphical abstract Highlights • A series of supported Au–Cu bimetallic catalysts with Au–CuO x nanohybrids are fabricated by a reduction–oxidation pretreatment strategy. • The catalyst Au–Cu/γ-Al 2 O 3 shows high selectivity to DMFD by oxidative esterification of HMF under 1 MPa O 2 at 100–120 °C without base. • The optimized catalyst Au–Cu/γ-Al 2 O 3 with Cu/Au atomic ratio at 1:1 affords the highest yield of 98% to DMFD and TOF value of 243 h–1. • The strong interaction between Au nanoparticles and CuO x species and their synergistic effect account for the enhanced performance. Abstract 5-Hydroxymethyl-2-furfural (HMF) is a key platform molecule for biomass utilization. The HMF derivative 2,5-furandicarboxylic acid (FDCA) by oxidation of HMF is a promising alternative for terephthalic acid as a monomer in polyethylene terephthalate. However, due to the facile purification of dimethyl furan-2,5-dicarboxylate (DMFD), an oxidative esterification derivative of HMF, is more desirable. In this work, supported Au–Cu bimetallic catalysts with Au–CuO x (x = 0–1) nanohybrids were prepared by a reduction–oxidation pretreatment strategy. The as-prepared catalysts were used for the oxidative esterification of HMF into DMFD under base-free conditions using oxygen as sole oxidant. Activity tests showed that the optimized Au–Cu/γ-Al 2 O 3 catalyst displayed a remarkably high DMFD yield of up to 98% and a turnover frequency (TOF) value of 243 h–1, whereas the monometallic Au and Cu catalysts exhibited poor performance. Various characterizations confirmed the strong interaction between Au nanoparticles and CuO x species, and their synergistic effect on the enhanced performance of HMF oxidative esterification. The reduction–oxidation pretreatment promoted the dispersion of CuO x and intensified the interaction of Au nanoparticles with CuO x. A plausible reaction mechanism for the oxidative esterification of HMF over Au–Cu/γ-Al 2 O 3 was proposed. This work provided new insights into the effect of reduction–oxidation pretreatment on the fabrication of supported Au–CuO x nanohybrids for the production of DMFD by HMF oxidative esterification. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal holds great promise to be the ideal anode for next-generation high-energy-density Li metal battery. However, the catastrophic dendritic Li propagation and the infinite relative volume change during cycling impede the implementation of Li metal anode. Herein, lithiophilic Li 22 Sn 5 with high ionic and electronic conductivity was in-situ implanted into metallic Li matrix via a scalable mechanical kneading operations and the subsequent heat treatment protocol. Homogeneous Li 22 Sn 5 framework in as-fabricated Li/Li 22 Sn 5 composite electrode effectively promoted the even distribution of Li+ flux and ions transport kinetics, thus suppressing the formation and growth of dendritic Li. Additionally, robust Li 22 Sn 5 alloy served as the ideal skeleton steadily endured the stress from the expansion and contraction of the electrode upon cycling, enabling an electrode structural integrity. As a result, the assembled full cell with coin-cell con Declaration of Interest Statementuration using high loading LiCoO 2 (16.6 mg cm−2) delivered an impressive capacity retention of 91.9 % for 100 cycles at 0.5 C with a low Negative/Positive (N/P) ratio of 3:1. The in-situ construction of lithiophilic alloy skeleton as a stable host provides an alternative approach for achieving long-lifespan Li metal battery. A thickness-controllable Li/Li 22 Sn 5 composite with in-situ formed lithiophilic Li 22 Sn 5 skeleton as the ideal host was fabricated via scalable mechanical kneading operations and the subsequent heat treatment protocols. The as-fabricated Li/Li 22 Sn 5 composite electrodes demonstrated superior electrochemical performance in full cells at a low Negative/Positive ratio. [Display omitted] [ABSTRACT FROM AUTHOR]