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H2O2 production by photocatalysis has received considerable attention, while using MOF‐based materials as photocatalysts is still less explored. Ligand functionalization of MOFs is a decoration way at the molecular level, which provides the basis for the further modification of MOFs. In this concept, ligand functionalization of MOFs for photocatalytic H2O2 production has been systematically and extensively discussed. The strategies of ligand functionalization include grafting of functional groups (e. g. amino, methoxyl, boron and alkyl) and multiple ligand decoration. Correspondingly, some specific effects are achieved, e. g. improved charge carrier separation, enhanced O2 adsorption and hydrophobicity, which can realize efficient H2O2 production by photocatalysis. Meanwhile, reaction conditions and activities of photocatalytic H2O2 production have also been explicitly introduced in these studies. At last, the future perspectives are proposed. This concept sheds fresh light on the great potential of ligand functionalization of MOFs for photocatalytic H2O2 production. [ABSTRACT FROM AUTHOR]

Ulcerative colitis (UC), a chronic and refractory nonspecific inflammatory bowel disease, affects millions of patients worldwide and increases the risk of colorectal cancer. Teprenone is an acylic polyisoprenoid that exerts anti-inflammatory properties in rat models of peptic ulcer disease. This in vitro and in vivo study was designed to investigate the effects of teprenone on UC and to explore the underlying mechanisms. Human intestinal epithelial cells (Caco-2 cells) serve as the in vitro experimental model. Lipopolysaccharide (LPS, 1 μg/mL) was employed to stimulate the production of pro-inflammatory cytokines (interleukin [IL]-6, IL-1β, and tumor necrosis factor [TNF]-α), Toll-like receptor-4 (TLR4), MyD88 expression, and NF-κB activation. A trinitrobenzene sulfonic acid (TNBS)-induced chronic UC rat model was employed for the in vivo assay. Pro-inflammatory cytokine stimulation by LPS in Caco-2 cells was inhibited by teprenone at 40 μg/mL through the TLR4/NF-κB signaling pathway. Teprenone attenuated TNBS-induced UC, decreased myeloperoxidase and malondialdehyde, induced TLR4 expression and NF-κB activation, and increased glutathione and zonula occludens-1 level in the rat colonic tissue. Moreover, Fusobacterium, Escherichia coli, Porphyromonas gingivalis elevation, and Mogibacterium timidum decline in UC rats were inhibited by teprenone. Based on our results, the protective effects of teprenone for UC may be related to its ability to modulate the gut microbiota and reduce the inflammatory response. [ABSTRACT FROM AUTHOR]

[Display omitted] • The whole advancement of MOF-based photocatalysts for H 2 O 2 production was discussed. • Diverse tailoring strategies on MOFs for H 2 O 2 production were summarized in detail. • H 2 O 2 production pathways, activities and reaction conditions were elucidated. • Outlooks on current challenges and emerging opportunities were presented. Photocatalytic synthesis of H 2 O 2 is currently in the spotlight because of its green and sustainable nature, but the construction of photocatalysts with high efficiency is still the key. In this regard, emerging photocatalysts based on metal–organic frameworks (MOFs) have been revitalized for the green synthesis of H 2 O 2 with the various acclaimed merits of MOFs. Therefore, this review provides an insight into the overall progress of MOF-based photocatalysts for H 2 O 2 production through various modification strategies on MOFs, including molecular-level decoration (ligand and metal center decoration, defect and facet engineering), heterostructure construction (C 3 N 4 /MOFs, metal sulfides/MOFs and metal oxides/MOFs) and derivatization (metal oxides/sulfides and carbonaceous materials). Meanwhile, the corresponding pathways (oxygen reduction reaction and water oxidation reaction), performances and reaction conditions for photocatalytic H 2 O 2 production were elucidated. Finally, outlooks on current challenges and emerging opportunities in this research field were presented. We hope this review will inspire and contribute to the future development of both MOF-based catalysts and H 2 O 2 green production. [ABSTRACT FROM AUTHOR]

Designing ultra‐light, green, and flexible films for efficient electromagnetic interference (EMI) shielding is crucial yet challenging. Herein, laminated Ti3C2Tx MXene nanosheets are prepared and impregnated into a delignified wood matrix to fabricate composite films. Through a facile drop‐casting and densification strategy, highly aligned cellulose fibers are used for regulating the stacking behavior of MXenes, and the MXenes are encapsulated and attached tightly to the cellulose chains through hydrogen bonds. A high MXene loading up to 32.5 wt.% can be realized, and the resultant MXene/wood film exhibits a tensile strength of 260.7 MPa. The EMI shielding effectiveness is calculated to be 55.5 dB (X‐band, 8.2–12.4 GHz), with a normalized surface‐specific shielding effectiveness of 2673.4 B cm2 g−1. Moreover, the superior electrical conductivity and structural robustness of the composite film give it pressure‐sensing properties and show high sensitivity for monitoring diverse human physiological movements. [ABSTRACT FROM AUTHOR]

Designing ultra‐light, green, and flexible films for efficient electromagnetic interference (EMI) shielding is crucial yet challenging. Herein, laminated Ti3C2Tx MXene nanosheets are prepared and impregnated into a delignified wood matrix to fabricate composite films. Through a facile drop‐casting and densification strategy, highly aligned cellulose fibers are used for regulating the stacking behavior of MXenes, and the MXenes are encapsulated and attached tightly to the cellulose chains through hydrogen bonds. A high MXene loading up to 32.5 wt.% can be realized, and the resultant MXene/wood film exhibits a tensile strength of 260.7 MPa. The EMI shielding effectiveness is calculated to be 55.5 dB (X‐band, 8.2–12.4 GHz), with a normalized surface‐specific shielding effectiveness of 2673.4 B cm2 g−1. Moreover, the superior electrical conductivity and structural robustness of the composite film give it pressure‐sensing properties and show high sensitivity for monitoring diverse human physiological movements. [ABSTRACT FROM AUTHOR]

• A mixed-linker method is used for creating defects in MIL-53(Al)-NH 2. • The presence of defects can finely tailor the acidity of catalyst. • A high glucose conversion of 98.3 % with a 5-HMF yield of 59.3 % is obtained. • The defective catalyst presents excellent recyclability and reusability. • The synergy of Lewis and Brønsted acid contributes to the superb performance. Developing functional catalysts with both Lewis and Brønsted acid sites is an essential task for achieving the direct conversion of glucose to 5-hydroxymethylfurfural (5-HMF), a process that is crucial for the sustainable production of renewable fuels and chemicals. In this work, a mixed-linker strategy is proposed to prepare defective MIL-53(Al)-NH 2 by introducing trifluoroacetic acid into the MIL-53(Al)-NH 2 synthesis process. The creation of defects facilitates the exposure and accessibility of Al3+ centers, as well as changes the coordination environment within the MIL-53(Al)-NH 2 skeleton. Both the number of Lewis and Brønsted acid sites are boosted, which is beneficial for glucose activation and 5-HMF generation. Through optimizing the reaction conditions, a glucose conversion of 98.3 % with a 5-HMF yield of 59.3 % was achieved by using defective 6d-MIL-53(Al)-NH 2 in a biphasic tetrahydrofuran/H 2 O NaCl system. Moreover, the 6d-MIL-53(Al)-NH 2 catalyst showed excellent recyclability and reusability, with its catalytic efficiency maintained almost unchanged for consecutive 10 cycles. The catalytic mechanism was elucidated and the acidity of the Lewis and Brønsted acid was modulated by defect engineering to achieve exceptional performance. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Research progress in the preparation of wood hydrogels by the top-down method is reviewed. • The advantages of wood hydrogels in structure and property are highlighted. • The relationship between wood hydrogel preparation-properties-applications is elucidated. • The challenges and outlooks for the future development are presented. Wood-based materials have attracted increasing interests due to the progress of wood nanotechnology. In such cases, wood hydrogels fabricated by a top-down approach demonstrate huge potential in smart electronics, sensors, biomedical and energy harvesting/storage devices. Distinct from cellulose or lignin hydrogels prepared from bottom-up technology, wood hydrogels retain the hierarchical/anisotropic structure of natural wood. In addition, wood hydrogels can be produced in a facile, scalable and energy-saving way. In this short review, a brief overview of the recent development of wood hydrogels is provided, with special emphasis on the preparation methods and structural characteristics. The various applications of wood hydrogels are then discussed from a preparation-performance-application point of view. This is followed by a summary of the challenges and perspective for the future improvement of wood hydrogels, as well as guidance for the development of green scalable wood-based functional polymeric materials. [ABSTRACT FROM AUTHOR]

Na 3 (VO) 2 (PO 4) 2 F (NVPOF) is considered as a promising cathode candidate for sodium-ion batteries (SIBs) owing to the high theoretical capacity and operating voltage. However, the challenges of its rate capability and cyclability limit its widespread application. Herein, the reduced graphene oxide decorated NVPOF microrods (NVPOF@G) are successfully synthesized by a facile hydrothermal-induced self-assembly procedure. It is found that the graphene oxides added act as a crystal nucleation growth regulator and provide rapid Na+ and electron transport in the electrodes. The prepared NVPOF@G microrods exhibit a superior rate capability of 82.2 mAh g−1 at 50 C (fast discharge in 72 s) as well as considerable long-term cycle stability with a capacity retention of 87.6% over 1000 cycles at 0.5 C. Even at 50 °C, the NVPOF@G still achieves a high reversible capacity of 109.4 mAh g−1 with a capacity retention of 87.7% after 1000 cycles. This microrod structure shows superior structural stability, even at high temperatures (50 °C). Such a cathode incorporates the benefits of batteries and supercapacitors. This work gives a way to fabricate microrod-structure phosphate-based materials for commercial applications in high-performance SIBs. [Display omitted] • An interpenetrated framework cathode of Na 3 (VO) 2 (PO 4) 2 F microrods and reduced graphene oxides is prepared. • The interpenetrated framework provides rapid Na+ and electron transport in the electrode. • The interpenetrated framework mitigates the crystalline stress and limits the subsequent corrosion by electrolytes. • The prepared cathode exhibits a superior rate capability of 82.2 mAh g−1 at 50 C. • The prepared cathode achieves a high capacity retention of 87.7% after 1000 cycles at 50 °C. [ABSTRACT FROM AUTHOR]

• Zeolitic imidazolate frameworks (ZIFs) with different dimensions were synthesized. • The electrochemical performance of ZIFs is dimensional-dependent. • One-dimensional ZIF performs best owing to the morphological and textural merits. So far, direct utilization of zeolitic imidazolate frameworks (ZIFs) as the electrode materials for high-performance supercapacitors (SCs) is challenging owing to their poor electrochemical performance. However, for the first time, the electrochemical activities of ZIFs are found to be dimensional dependent in this study, and can be greatly boosted by reducing the dimension from three-dimension (3D) or two-dimension (2D) to one-dimension (1D). The unique 1D architecture endows 1D ZIF with improved conductivity as well as a high surface-to-volume ratio to facilitate the accessibility of electrolyte ions. Additionally, 1D ZIF is highly defective with abundant linker-missing defects, leading to the favorable exposure of cobalt ions as the redox active sites responsible for pseudocapacitance. Benefiting from these structural and textural merits, 1D ZIF exhibits a much higher charge storage capacity, rate capability and cycling stability than 2D and 3D ZIF. When assembled with activated carbon (AC), the asymmetric supercapacitor device (1D ZIF//AC) can deliver an impressive energy density of 76 Wh kg−1 at a power density of 800 W kg−1, superior to many other ZIFs, ZIF-based composites, ZIF-derived carbon, and even some advanced metal compounds reported in literature. [Display omitted] [ABSTRACT FROM AUTHOR]

Interest in production and utilization of 5-hydroxymethylfurfural (5-HMF) has risen greatly as 5-HMF is considered as an extremely important platform compound. It remains a huge challenge to develop efficient and low-cost solid catalysts with suitable acid properties for sustainable production of 5-HMF from glucose. Herein, a bifunctional Sn-modified SBA-15 (Sn–OH/SBA-15) catalyst containing both Lewis and Brønsted acid sites was fabricated. Dimethyldichlorostannane was grafted onto mesoporous SBA-15, and the methyl groups were then converted to hydroxyl groups by calcination. The synergistic effects of Lewis and Brønsted acid significantly boosted the synthesis of 5-HMF from glucose adopting the one-pot method. By optimizing the reaction conditions, the Sn–OH/SBA-15 sample was able to achieve a glucose conversion of 96.9% with a 5-HMF yield of 70.6% (180 °C, 5 h). Moreover, the catalyst demonstrated superior recyclability and reusability. This work would enlighten the exploitation and preparation of highly efficient catalysts for the transformation of carbohydrates into value-added chemicals. [Display omitted] • Solid catalyst is used for transformation of glucose to 5-HMF. • Mesoporous structure and appropriate acid sites favor the production of 5-HMF. • A high 5-HMF yield of 70.6% is achieved by adding Sn–OH/SBA-15. [ABSTRACT FROM AUTHOR]

A Co-MOF-74-derived DS-CoSe 2 @C-600 hybrid was designed to unite the merits of both hollow double-shell structure and plum pudding-like structure for optimized electrochemical Na+ storage performance. [Display omitted] • The formation mechanism of hollow doubel-shell MOF-74 is elaborated. • Hollow doubel-shell CoSe 2 @C hybrid shows superior Na+ storage performance. • Electrochemical Na+ storage performance is discussed in detail. Designing an intelligent metal selenides/carbon hybrid assembly is considered to be a very feasible strategy to maximize the potential of metal selenides and carbon materials for electrochemical Na+ storage. Herein, we prepare a hollow double-shell Co-MOF-74-derived CoSe 2 @carbon hybrid in which plenty of ultrafine CoSe 2 nanoparticles are encapsulated within carbon matrix, and such a unique CoSe 2 @carbon hybrid is able to take advantages of both hollow double-shell structure and plum pudding-like structure, which facilitate fast electrochemical kinetics and high tolerance to volumetric strain. As a result, the prepared hollow double-shell CoSe 2 @carbon hybrid exhibits a reversible capacity of 223.4 mAh/g at a very high current density of 10 A/g for Na+ storage, and also holds 92.3 % of capacity retention after 5000 cycles at 2 A/g. This work has provided a useful enlightenment for developing high-efficiency electrode materials in the electrochemical Na+ storage field. [ABSTRACT FROM AUTHOR]

A cellulose-reinforced eutectogel was constructed by deep eutectic solvent (DES) and cotton linter cellulose. Cellulose was dispersed in the ternary DES consisting of acrylic acid, choline chloride and AlCl 3 ·6H 2 O. The photoinitiator was then introduced into the system to in situ polymerize acrylic acid monomer to form transparent and ionic conductive eutectogels while keeping all the DES. The crosslinks formed by Al3+ induced ionic bonds and reversible links formed by hydrogen bonds give the eutectogels high stretchability (3200 ± 200 % tensile strain), self-adhesive (52.1 kPa to glass), self-healing and good mechanical strength (670 kPa). The eutectogels were assembled into sensors and epidermal patch electrodes that demonstrated high quality human motion sensing and physiological signal detection (electrocardiogram and electromyography). This work provides a facile way to design flexible electronics for sensing. [ABSTRACT FROM AUTHOR]

• The cellulose hydrogel is modified by photocatalyst CuS@MIL-100 (Fe). • CuS@MIL-100 hybrids facilitate photothermal and photocatalysis. • The hydrogel evaporator shows an evaporation rate of 2.37 kg m−2 h−1. • The hydrogel is used for clean water production from seawater and wastewater. A hydrogel solar evaporator is constructed by depositing photocatalysts into a cellulose matrix. The photocatalyst consists of copper sulfide (CuS) and Fe-based metal–organic framework (MIL-100(Fe)), with CuS particles loaded on MIL-100(Fe). By combining CuS@MIL-100 composites into cellulose hydrogel, the hydrogel solar evaporator can be acquired. The optimal evaporator exhibits an evaporation rate of 2.37 kg m-2h−1 at 1 kW m−2, with an evaporation efficiency of 94.4%. Moreover, the composite hydrogel can produce clean water from wastewater by coupling photothermal effects and photocatalytic degradation. The composite hydrogel exhibits a photocatalytic degradation efficiency of 97.3% for methylene blue (a typical dye contaminant) and 93.3% for tetracycline (a typical antibiotic). This work provides ideas for designing and manufacturing the next-generation of solar-powered water purification systems. [ABSTRACT FROM AUTHOR]

In this work, Amine-functionalized CNF/UiO-66 (CNF–NH 2 /UiO-66) composite membranes were fabricated by incorporating UiO-66 nanoparticles in the CNF–NH 2 matrix. The CO 2 -facilitated transfer channels can be constructed in the CNF–NH 2 /UiO-66 composite membrane. As a natural polymer material, CNF–NH 2 would absorb water and form a gel-like structure under humidification. The adsorbed water can convert CO 2 into bicarbonate ions (HCO 3 −) through the catalysis of amino groups on CNF–NH 2. Moreover, in CNF–NH 2 /UiO-66 composite membranes, HCO 3 − could quickly migrate to the permeate side promoted by the porous UiO-66, facilitating CO 2 transport. The optimum membrane gave a CO 2 permeability of 257.0 Barrer with a CO 2 /CH 4 ideal selectivity of 71.3. [Display omitted] • Hydrogel material CNF–NH 2 was selected as membrane matrix for gas separation. • Adsorbed water molecules can act as fast moving carriers of CO 2. • Porous UiO-66 was incorporated in CNF–NH 2 matrix as a highway for CO 2 transport. • Significantly higher CO 2 permeability was observed for membranes in a humid state. [ABSTRACT FROM AUTHOR]

Interfacial evaporation through hydrogel-based evaporators is emerging as a sustainable and cost-effective strategy for drinkable water production. Herein, a specially designed bi-layer hydrogel evaporator was fabricated and used for efficient solar water desalination. With cotton linter as cellulose precursor, it was dispersed in a highly concentrated ZnCl 2 (65 %) solution, and cross-linked by epichlorohydrin to prepare cellulose composite hydrogel. After removing inorganic salts by salt-leaching, polyaniline (PANi) with broadband and wide-range light absorption was then integrated into the top surface of hydrogel through in situ polymerization to construct a bi-layer evaporator. As a solar evaporator, the water could be evaporated with a low-energy demand, and the heat from the sunlight could be confined at the interface to achieve efficient water evaporation. Therefore, the hydrogel evaporator demonstrates an optimal water evaporation rate of 3.02 kg m−2 h−1 and photothermal conversion efficiency of 89.09 % under 1 sun (1 kW m−2) irradiation. This work provides new possibilities for efficient solar water purification systems with assured water quality. [Display omitted] [ABSTRACT FROM AUTHOR]