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[Display omitted] Self-supporting tree skeleton and densely stackable phenolic resin are cleverly coupled together by a "rebar-concrete" structure. The thick electrode as a master of space utilization has extremely high areal and volumetric energy density. This work confirms the effective coupling of the self-supporting skeleton and powder materials, providing novel ideas for the preparation of thick electrodes with high mass loading. • A "rebar-concrete" structure is proposed to facilitate the high space utilization of thick electrodes. • The areal capacitance of the thick electrode reaches an astonishing 11F cm−2. • The assembled SSC device delivers competitive areal energy density of 0.63 mWh cm−2. The thick electrode design with high packing density of active materials can increase the capacity in a limited space. However, the key challenge is still to develop a system with high space utilization and ensure electron/ion transport in thick electrode. This work proposes an interesting "rebar-concrete" structure, which successfully prepared wood/phenolic resin-derived thick electrode with high space utilization by in-situ polymerization of phenolic resin (concrete) in the wood (rebar) channel. The electrode exhibits an excellent three-dimensional interconnected hierarchical pore structure due to the uniform activation of in-situ anchored KOH particles. The mass loading (35 mg cm−2) and areal capacitance (11F cm−2) of the obtained composite electrode are increased to 446 % and 1257 % of the original balsa wood, respectively. The assembled symmetric supercapacitor (SSC) exhibits a high energy density of 0.63 mWh cm−2 (3.91 mWh cm−3) and an excellent cycle stability (95 % retention after 50 000 cycles), showing good practicability in lighting LEDs or driving a fan. This strategy achieves effective coupling of self-supporting skeleton and powder materials, providing more insights and possibilities for the preparation of high energy density thick electrodes. [ABSTRACT FROM AUTHOR]

In recent years, single‐atom catalysts (SACs) have become the most active part of the catalytic field due to their excellent catalytic activity. Among them, Ru SACs exhibit excellent performance in many catalytic applications due to their high atomic utilization efficiency, catalytic activity and selectivity, and relatively low cost. In order to understand the structure–performance relationship and potential catalytic mechanism of Ru SACs, this review summarizes the research progress of Ru SACs in the fields of electrocatalytic water splitting, fuel cells, nitrogen reduction, and nitrate reduction in recent years. The catalytic process of Ru single atom in different synthesis methods and modification strategies is summarized. Finally, some opportunities and challenges for the future development of Ru SACs are prospected. [ABSTRACT FROM AUTHOR]

Conductive hydrogels have emerged as excellent candidate materials for designing and fabricating flexible wearable sensors. However, there are still critical challenges in preparing high-performance, strongly adhesive, and biocompatible hydrogels through robust and green strategies. A central issue is the lack of an efficient, environmentally friendly and adaptable catalytic system for hydrogel construction. Herein, a series of natural polyphenol/Fe3+ nanodots (PPL/Fe3+ NDs) has been developed as nanoreactors to catalyze the self-gelation of vinyl monomers. The NDs could provide confined spaces for electron transfer, achieving an exceptionally high catalytic efficiency. Remarkably, they were effective in promoting the polymerization of vinyl monomers to form hydrogels even at the Fe content as low as 0.13 μg mL−1. The resulting hydrogels exhibited outstanding mechanical properties, excellent adhesive capacity, stable ultraviolet (UV)-shielding ability, and feasible electrical conductivity. These advantages allow the hydrogel as a flexible wearable sensor to monitor various human motions. It is believed that these natural polyphenolic NDs could open up new possibilities for the advancement of conductive hydrogels and contribute to the design and implementation of human–machine interaction devices. [ABSTRACT FROM AUTHOR]

Recently, there has been a growing demand for ultra‐thin carbonized wood films (CWF) with high shielding efficiency (SE) to replace non‐renewable alternatives. Researchers aim to enhance electromagnetic (EM) wave absorption and improve electromagnetic interference (EMI) SE in CWF materials to reduce secondary pollution from reflected EM waves. In this work, the carbonized wood composite film (CWF/EP/Co) with a thickness of 120 µm through the process of hot‐pressing and carbonizing wood soaked in a mixed solution of water‐borne epoxy (EP) and Co/Zn‐MOF (ZIF‐67/8) is obtained. The CWF/EP/Co film exhibits excellent conductivity (105 S cm−1) and demonstrates an excellent EMI SE (73 dB) at a 200 µm thickness. Remarkably, the specific EMI shielding effectiveness (SSE/t) of CWF/EP/Co films reached 15833.3 dB·cm2·g−1 in the X‐band, making it the highest reported value among all wood‐derived EMI shielding materials. CWF/EP/Co films have a high absorption coefficient (A) of 0.4, indicating their effectiveness in absorbing EM waves. Furthermore, the EMI shielding effect of the large‐scale wallpaper (170 mm×170 mm) is confirmed by finite element analysis. Additionally, the CWF/EP/Co film exhibits good mechanical properties and effective Joule heating performance. This shielding film shows promise in applications such as buildings and smart homes, providing EMI shielding and warming effects. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel 3D COF (SPB-HHTP-DBF) is synthesized, as the first introduction of spiroborate structures into environmental engineering. • Major cationic dyes including methylene blue (MB), crystal violet (CV), and malachite green (MG) removal of 99% within 10 min. • Highly selective separation of cationic dyes from mixed anionic/cationic dye solutions, advanced adsorption capacity and reliable cycling stability. Covalent organic frameworks (COFs) are undergoing a period of rapid development of novel structures and diverse functions. Ionic COFs have been applied in environmental engineering due to their porous, robust and charged skeleton, making it necessary to expand the family of ionic frameworks. Based on an in-situ functionalization strategy, we report a new 3D anionic COF constructed by the linker 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP), linkage spiroborate (SPB) and counter cation [ n -Bu 2 NH 2 ]+ (DBA). Anionic spiroborate centers are distributed in a 4-fold interpenetrated network of srs topology, constituting a stable crystalline structure. The framework has been used for adsorption of charged dyes and present rapid cationic dyes removal(over 99 % within 10 min), effective adsorption capacities for methylene blue (MB), crystal violet (CV), and malachite green (MG) (maximum values of 892 mg g−1, 1632 mg g−1 and 457 mg g−1, respectively), impressive molecular sieving selectivity (little absorption of anionic dyes) and good recycle performance (no removal loss for at least 5 cycles). In addition, the adsorption behaviors of isotherm and kinetic are discussed. This study not only reveals a new strategy for constructing ionic 3D COFs, but also contributes to their development for environmental engineering related applications. [ABSTRACT FROM AUTHOR]

High-performance porous polyimide (PI) monoliths, including PI aerogels, sponges, and foams, have become one of the hotspots in both researching and applications due to their superior properties such as high porosity, outstanding mechanical and thermal stability, low dielectric constant and thermal conductivity. Up to now, various fabricating methods and applicating situations for PI porous monolith materials have been reported. From the viewpoint of molecular chemistry, porous structure construction, as well as the functional modification, the property optimization and adjustment are feasible, endowing PI monoliths with promising potential for different practical applications (e.g. sensors, low-k materials, thermal management, energy field and utilization, absorption and filtration, photonic utilization, etc.). In this review, the recent progress of porous PI monoliths was summarized in detail based on the fabrication methods, functional modifications, as well as multi-functional applications. Besides, the future perspectives of this field were also provided for reference. Apart from presenting an overview of progress made in the field of PI porous monoliths, this review could also be meaningful for those researching topics which have similarity within. [ABSTRACT FROM AUTHOR]

As a convenient photothermal material, polydopamine (PDA) has been widely utilized in wood-based evaporators. However, the loading conditions of polydopamine on biomass bulk materials have not been systematically studied. In this paper, the suitable reaction conditions of polydopamine were studied with rattan as the substrate, and a reference for the improvement of the loading conditions was proposed. The polydopamine-loaded rattan-based evaporator (PDA-R) prepared on this basis exhibits excellent working stability due to the unique large-scale hierarchical porous structure of rattan. In addition to excellent salt resistance and cycle performance (evaporation rate decays by 5.1% after 30 cycles), the larger-aperture channel (200–450 μm) also brings better adaptability to salinity changes than polydopamine-loaded basswood-based evaporator (PDA-BW) (the attenuation coefficient of PDA-R is 6.2%, while the attenuation coefficient of PDA-BW is 16.3%). All of these indicate the broad prospects of polydopamine-loaded rattan-based evaporator as a multi-effect treatment scheme of brine. [Display omitted] • Loading conditions of polydopamine on biomass block material is systematic studied. • PDA-R has excellent salt resistance and cycling performance in high salinity brines. • PDA-R has great adaptability to salinity changes. • The effect of uniformly dense pore size of the substrate on salinity adaptability of evaporator is explored. [ABSTRACT FROM AUTHOR]

The development of robust and bioinspired adhesives with excellent performances including fast gel time, low cost, good adhesion strength and stability, and excellent solvent and temperature resistance against harsh environment is urgent for practical applications. In this paper, kinds of natural polyphenolic adhesives have been successfully fabricated via the multiple polyphenol-diisocyanate cross-linking (PDC) reactions between natural polyphenols (extracts) and diisocyanate molecules. Under heating, as-prepared adhesives could effectively adhere onto a wide range of substrates (i.e. PTFE, PET, PMMA, Al, Cu, paper, glass, wood) through hierarchical interactions. Moreover, these adhesives exhibited great adhesion stability against complex solvents and low-temperature environments, whose adhesion strength could remain unchanged after soaking solvents after 30 days, which was conducive to their potential applications in industry and chemical fields, including petroleum, wood, metal, glass, plastics, and rubber adhesion. We believed that this work would provide new strategies towards the preparation of robust adhesives with excellent resistant against various solvents and low temperature for many fields by using naturally occurring building blocks. Natural polyphenolic adhesives were successfully fabricated via the multiple polyphenol-diisocyanate cross-linking (PDC) reactions between natural polyphenols (extracts) and diisocyanate molecules. Under heating, as-prepared adhesives could effectively adhere to a wide range of substrates (i.e. PTFE, PET, PMMA, Al, Cu, paper, glass, wood) through hierarchical interactions. Moreover, these adhesives exhibited great adhesion stability against complex solvents and low-temperature environments, and the adhesion strength could even remain unchanged after soaking solvents after 30 days. [Display omitted] • Natural polyphenolic adhesives were successfully fabricated. • As-prepared adhesives could effectively adhere to various substrates. • These adhesives exhibited great solvents and low-temperature resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two basic design strategies for 3D COFs: high valency and functionalization. • 3D COFs: building blocks, topology, linkage, and PSM strategy. • Applications in adsorption and separation, catalysis, stimulus response, conduction and energy storage. • The challenges and opportunities are proposed for future research. Covalent organic frameworks (COFs) are a class of porous crystalline organic materials. The dynamic chemistry of covalent bonding and the applications of COFs have made great progress already. Three-dimensional (3D) COFs have attracted much attention in recent years because of their more diverse spatial structures and interconnected pore properties. High valency and functionalization are two key strategies of 3D COFs design, including the development of building blocks, topology, linkage and post synthetic modification strategy. As a result, the diversity of COF spatial structures is significantly extending and various applications in energy, environment, biology and chemical catalysis are developing. In this review, we summarized the recent articles about 3D COFs in the field of framework design, function development and applications, and put forward the critical strategies and comment, the future perspectives of the field are also prospected. [ABSTRACT FROM AUTHOR]

Herein, we used a one-pot method to fabricate a novel MOF-on-MOF adsorbent, namely MOF(Zr)-on-MOF(Ce). The adsorbent demonstrated a high maximum fluoride-ions capture capacity of 164.47 mg g−1. The morphology, elemental distribution, pore size distribution, and thermal stability were studied using SEM-EDS, XRD, BET, and TGA. The influence of the temperature, solution pH, fluoride concentration, and coexisting ions was explored using intermittent experiments. The results suggested that MOF(Zr)-on-MOF(Ce) had a fast capture rate for fluoride. MOF(Zr)-on-MOF(Ce) maintained an excellent fluoride removal performance over a wide pH range with an initial fluoride concentration of 20 mg L−1. The optimal effect was obtained at a pH of 4, but a high removal efficiency of 94% was maintained even at a pH of 9. Interference experiments showed that only the PO 4 3– had an adverse inhibition influence. The field experiments demonstrated that MOF(Zr)-on-MOF(Ce) can keep the safety threshold levels of fluoride in drinking water. The Langmuir and pseudo-second order kinetic models were well fitted for the defluoridation process, demonstrating that the adsorption of fluoride ions on MOF(Zr)-on-MOF(Ce) was dominated by monolayer chemisorption. With the further characterization and kinetic thermodynamic studies indicates that the removal mechanism involves ion exchange, electrostatic interactions and complexation effect. [Display omitted] • A novel MOF(Zr)-on-MOF(Ce) adsorbent were fabricated via one-pot methods for defluorination. • The maximum adsorption capacity of MOF(Zr)-on-MOF(Ce) was 164.47 mg g–1 for F ions. • The adsorbent had an excellent defluoridation performance with a wide pH range. • The mechanisms are ion-exchange, electrostatic interaction and complexation effect. [ABSTRACT FROM AUTHOR]

Nanocellulose, as a nanoscale polymer material, has garnered significant attention worldwide due to its numerous advantages including excellent biocompatibility, thermal stability, non-toxicity, large specific surface area, and good hydrophilicity. Various methods can be employed for the preparation of nanocellulose. Traditional approaches such as mechanical, chemical, and biological methods possess their own distinct characteristics and limitations. However, with the growing deterioration of our living environment, several green and environmentally friendly preparation techniques have emerged. These novel approaches adopt eco-friendly technologies or employ green reagents to achieve environmental sustainability. Simultaneously, there is a current research focus on optimizing traditional nanocellulose preparation methods while addressing their inherent drawbacks. The combination of mechanical and chemical methods compensates for the limitations associated with using either method alone. Nanocellulose is widely used in wound dressings owing to its exceptional properties, which can accelerate the wound healing process and reduce patient discomfort. In this paper, the principle, advantages and disadvantages of each preparation method of nanocellulose and the research findings in recent years are introduced Moreover, this review provides an overview of the utilization of nanocellulose in wound dressing applications. Finally, the prospective trends in its development alongside corresponding preparation techniques are discussed. [ABSTRACT FROM AUTHOR]

• A green and common method was proposed to prepare biomimetic actuators. • The PNPB actuator showed excellent multi-stimulus response and synergistic effect. • Anisotropic natural bamboo endowed the PNPB actuator programmable performance. • The PNPB actuator had application potential in complex environment. Hydrogel actuators with controllable deformation and excellent biocompatibility are widely used in soft robot, valve, drug delivery and lenses. However, the stimulation response performance of existing hydrogel actuators mostly focuses on a single active layer, which greatly affects its driving performance and service life. In this work, we integrate temperature-responsive hydrogel (Poly (N-isopropyl acrylamide), PNIPAM) and pH-responsive hydrogel (polyacrylic acid, PAAc) into one system to fabricate a dual active layer composite hydrogel actuator with high performance. Based on the PAAc hydrogels achieving contract or expand at different pH values, the obtained actuator exhibits admirable bidirectional bending characteristics. In addition, the anisotropic bamboo sheet endows the hydrogel actuator with programmable 3 D complex deformation. Benefitting from the synergy and different responsiveness between the two active layers, the hydrogel actuator not only has multiple response performance, but also greatly improves its deformation degree and response speed. More importantly, these promising properties of the actuator have broad application prospects in the development of pattern design and intelligent switch. This work proposes a promising strategy for the structural design of hydrogel actuators with excellent performance, and encourages more exploration of the application range of the actuator. [ABSTRACT FROM AUTHOR]