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Microcrystalline cellulose (MCC) is hydrolyzed to an appreciable extent (70 %) by using 1-(4-sulfonic acid) butyl-3-methylimidazolium hydrogen sulfate (IL-1) as effective catalyst. Valuable chemicals, such as 5-hydroxymethyl furfural (HMF) and furfural, are obtained in relatively high yields (15 % and 7 %, respectively). Interestingly, the introduction of FeCl₂ as catalyst into IL-1 further enhances the catalytic activity, as proved by the higher conversion of MCC (84 %) and higher yields of HMF and furfural (34 % and 19 %, respectively) under the same experimental conditions, although small amounts of levulinic acid (LA) and total reducing sugars (TRS) were also found. The hydrolysis of MCC scarcely proceeded, or showed a lower efficiency, in the absence of catalyst (4 %) or with Al₂O₃ (7 %), inorganic acids (≤65 %), or several other ionic liquids (≤24 %) as catalyst. Dimers of furan compounds were detected as the main byproducts, as analyzed by HPLC-MS; from the mass spectrometry analysis, the components of the gas-phase products were determined to be methane, ethane, CO, CO₂, and H₂. A mechanism to explain the high activity of FeCl₂ in the IL-1 system is proposed. Recycling of the IL-1 catalyst showed an almost constant activity during five successive trials. The simple and effective catalyst system may prove valuable in facilitating the energy-efficient and cost-effective conversion of biomass into biofuels and platform chemicals.

Graphene oxide (GO), prepared by the modified Hummers method, was applied as a highly active and selective solid acid catalyst for oxidative transformation of furfural (FAL) into succinic acid (SA) with H2O2 as the oxidant. Over a GO catalyst, 88.2% yield of SA from FAL was achieved under relatively mild reaction conditions. By characterization of the prepared GO and various control experiments, the higher efficiency of GO than conventional catalysts was attributed to its unique atomic layered structure and suitable acidity. On the basis of the results in this work and previous reports, a reasonable reaction pathway was proposed. Different from other acid catalysts, it was suggested that the aromatic rings in GO and the edges decorated with −SO3H groups worked synergistically in FAL oxidation. The GO catalyst was found reusable, and only a slight decrease in the catalytic activity was observed after six cycles.

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Designing scalable coatings with a wide spectrum of functions such as liquid repellency, anticorrosion, and antiflaming and a high level of mechano–chemical–thermal robustness is crucial in real‐life applications. However, these individual functionalities and robustness are coupled together or even have conflicting requirements on the interfacial or bulky properties of materials, and thus, simultaneously integrating all these individual features into one coating has proved challenging. Herein, an integral skin‐inspired triple‐layered coating (STC) that resolves conflicting demands imposed by individual features on the structural, chemical, mechanical, and thermal properties of materials is proposed. Specifically, the rational design of multiple gradients in roughness, wetting, strength, and flame retardancy and the formation of continuous interfaces along its triple layers endow a sustained liquid repellency, anticorrosion, and flame retardancy even under harsh environments, as well as strong antiabrasion on surfaces and adhesion with the substrate. Such an all‐in‐one design enhances the durability and lifetime of coatings and reduces the maintenance and repair, thereby contributing to cost and energy saving. Together with a facile spraying fabrication process, this STC provides a feasible and sustainable strategy for constructing energy and resource‐saving materials.