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The efficient utilization of lignocellulosic biomass has tremendous potential to reduce the excessive dependence on fossil fuels. Here, we provide an overview on the recent achievements in the catalytic production of value-added chemicals and fuels. When targeting chemicals, a key objective is to maximize the product selectivity to favor the subsequent separation. This can be achieved through the design of catalysts and optimization of catalytic systems based on the deep understanding of the catalytic mechanism. For production of fuels, attention should be paid to the establishment of an energy-efficient process for high-quality fuels. This can be realized through the design of C-C coupling reactions and the development of multifunctional catalysts to minimize the reaction steps from lignocellulose to fuels. In addition, the full utilization of lignocellulose into biofuels and chemicals in a single process is separately introduced. Finally, several personal perspectives on the opportunities and challenges within this promising field are discussed.

The upgrading of plastic waste is one of the grand challenges for the 21 st century owing to its disruptive impact on the environment. Here,w es howt he first example of the upgrading of various aromatic plastic wastes with C À Oand/or C À Cl inkages to arenes (75-85 %y ield) via catalytic hydrogenolysis over aR u/Nb 2 O 5 catalyst. This catalyst not only allows the selective conversion of single-component aromatic plastic,a nd more importantly,e nables the simultaneous conversion of am ixture of aromatic plastic to arenes.T he excellent performance is attributed to unique features including:(1) the small sized Ru clusters on Nb 2 O 5 ,whichprevent the adsorption of aromatic ring and its hydrogenation;(2) the strong oxygen affinity of NbO x species for C À Ob ond activation and Brønsted acid sites for CÀCb ond activation. This study offers ac atalytic path to integrate aromatic plastic waste back into the supply chain of plastic production under the context of circular economy.

Conversion of lignin into monocyclic hydrocarbons as commodity chemicals and drop-in fuels is a highly desirable target for biorefineries. However, this is severely hindered by the presence of stable interunit carbon-carbon linkages in native lignin and those formed during lignin extraction. Herein, we report a new multifunctional catalyst Ru/NbOPO4 that achieves the first example of catalytic cleavage of both interunit C-C and C-O bonds in one-pot lignin conversions, yielding 124-153% of monocyclic hydrocarbons; that is 1.2-1.5 times those yields obtained from the established nitrobenzene oxidation method. This catalyst also exhibits high stability and selectivity (up to 68%) to monocyclic arenes over repeated cycles. The mechanism of the activation and cleavage of 5-5 C-C bonds in biphenyl, as a lignin model adopting the most robust C-C linkages, has been revealed via in situ inelastic neutron scattering, coupled with modelling. This study breaks the conventional theoretical limit on lignin monomer production.

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Sulfur is an important electrode material in metal−sulfur batteries. It is usually coupled with metal anodes and undergoes electrochemical reduction to form metal sulfides. Herein, we demonstrate, for the first time, the reversible sulfur oxidation process in AlCl3/carbamide ionic liquid, where sulfur is electrochemically oxidized by AlCl4− to form AlSCl7. The sulfur oxidation is: 1) highly reversible with an efficiency of ~94%; and 2) workable within a wide range of high potentials. As a result, the Al−S battery based on sulfur oxidation can be cycled steadily around ~1.8 V, which is the highest operation voltage in Al−S batteries. The study of sulfur oxidation process benefits the understanding of sulfur chemistry and provides a valuable inspiration for the design of other high-voltage metal−sulfur batteries, not limited to Al−S configurations.

Base-free aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) was realized successfully based on the design of a novel Pt/C–O–Mg catalyst.

The production of hydrogen from the aqueous-phase reforming (APR) of oxygenated hydrocarbons is promising. Herein, the performances of Pt loaded on NiAl2O4 spinel and γ-Al2O3 were investigated in the APR of methanol. The conversion of methanol and the yield of hydrogen over Pt/NiAl2O4 reached 99.9% and 95.7%, respectively. In comparison with Pt/γ-Al2O3 catalyst (26.5% and 23.3%, respectively), these values were enhanced by 4-fold. More importantly, Pt/NiAl2O4 had high stability with only 10% loss of its initial conversion after 600 h on stream. In situ diffuse reflectance infrared Fourier transform spectra (DRIFTS) of the APR of methanol revealed that the reaction underwent the dehydrogenation of methanol and the sequential water–gas shift (WGS) reaction. These two reactions were then investigated independently, in which Pt/NiAl2O4 showed more efficient performance than Pt/γ-Al2O3. Intensive characterization methods revealed that the chemical state of Pt played a pivotal role in the dehydrogenation of methanol to generate the adsorbed CO intermediate. For Pt/NiAl2O4 catalyst, the reduction of PtO x to metallic state Pt was easier because of the presence of the oxygen vacancy, leading to the higher catalytic performance in the dehydrogenation of methanol. Further studies with in situ DRIFTS-MS of WGS demonstrated a redox mechanism over Pt/NiAl2O4 catalyst, which was different from the associative route that occurred over Pt/γ-Al2O3 and made the WGS reaction faster. The addition of Ni (NiAl2O4 spinel) creates oxygen vacancies, giving WGS which underwent a redox route. This work presents the deep understanding into the pathway and mechanism in the APR of methanol and is expected to have important implications for the future development of APR catalysts.