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Aqueous Zn ion batteries (ZIBs) are one of the most promising battery chemistries for grid‐scale renewable energy storage. However, their application is limited by issues such as Zn dendrite formation and undesirable side reactions that can occur in the presence of excess free water molecules and ions. In this study, a nanocellulose‐carboxymethylcellulose (CMC) hydrogel electrolyte is demonstrated that features stable cycling performance and high Zn2+ conductivity (26 mS cm−1), which is attributed to the material's strong mechanical strength (≈70 MPa) and water‐bonding ability. With this electrolyte, the Zn‐metal anode shows exceptional cycling stability at an ultra‐high rate, with the ability to sustain a current density as high as 80 mA cm−2 for more than 3500 cycles and a cumulative capacity of 17.6 Ah cm−2 (40 mA cm−2). Additionally, side reactions, such as hydrogen evolution and surface passivation, are substantially reduced due to the strong water‐bonding capacity of the CMC. Full Zn||MnO2 batteries fabricated with this electrolyte demonstrate excellent high‐rate performance and long‐term cycling stability (>500 cycles at 8C). These results suggest the cellulose‐CMC electrolyte as a promising low‐cost, easy‐to‐fabricate, and sustainable aqueous‐based electrolyte for ZIBs with excellent electrochemical performance that can help pave the way toward grid‐scale energy storage for renewable energy sources. [ABSTRACT FROM AUTHOR]

This research uses physical mixing and twin‐screw extrusion process to prepare biomass activated carbon (BAC)/ultra‐high molecular weight polyethylene (UHMWPE) composite materials. The mechanical properties, micro‐morphology, and thermodynamic properties of the composite materials were explored. The experimental results show that the tensile strength of 65% activated carbon added to the composite material has changed from 22.93 to 97.65 MPa, which is an increase of 325.86%. According to the Scanning electron microscope (SEM) image, a schematic diagram of the internal combination of the composite material is made, the concept of a three‐dimensional network interpenetrating three‐dimensional structure is proposed, and the mechanism of tensile properties enhancement is explained. Obviously, as the carbon content increases, the storage modulus (E′) also increases, and the loss factor (tan δ) and glass transition temperature (Tg) also change. The ability of composite materials to resist pyrolysis has also been enhanced. The above results indicate that BAC as a filler of composite materials can improve various performances. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bilayer evaporator composed of MOFs-derived carbon on wood sponge is prepared. • The designed architectures boost the solar-thermal interfacial evaporation performance. • The evaporator can extract groundwater from low moisture environment. Soil-water extraction based on interfacial solar-thermal technology is a promising strategy to provide affordable freshwater in remote and poor inland areas. A double-layer solar evaporator is prepared on a wood sponge with a one-step brush-printing coating of zeolitic imidazolate framework-8 (ZIF-8)-derived nanostructured carbon. In this typical architecture, the ZIF-8-derived carbon coating inherits the original porous, dodecahedral framework, thus forming a chapped, rough morphology that synergistically promotes photothermal conversion. Wood sponges manufactured from raw wood offer privileged water-extraction advantages, including an abundance of super hydrophilic channels that ensure efficient bulk-water pumping and steam release. The double-layer solar evaporator shows high sunlight absorbance (∼97.8 %), low thermal conductivity (0.12 W m−1 K−1), stronger capillary force, and rapid water transport (30 cm min−1). Consequently, apparent pure water-evaporation and soil water-extraction rates reach 1.42 and 0.57 kg m-2h−1 under a one-sun light intensity, respectively. Therefore, the ZIF-8-based wood sponge can efficiently achieve interfacial evaporation and soil water extraction, providing a novel pathway for obtaining clean drinking water in arid inland areas. [ABSTRACT FROM AUTHOR]

Herein, chitosan-based hydrogel beads (CHBs) were used to prepare N- and O-enriched hierarchical porous carbon (PC) by microwave heating for only 10 min. Water molecules in CHBs can act as heating carriers, and the resulting steam not only squeeze out air to create an oxygen-free atmosphere but act as physical activating agent to generate pores. Furthermore, the increased temperature contributed to form chitosan-based char, which, in turn, facilitated microwave absorption to further increase temperature. Considering that KOH as gelling agent of CHBs can also generate pores, the effect of KOH concentration on physicochemical properties of PCs was investigated in detail. Significantly, appropriately higher KOH concentration (3–7%) would cause fiercer reactions to achieve more developed porous structure, while excessive KOH concentration (10%) led to over-etching phenomenon and limited the further development on porous structure. The obtained PCs exhibited large specific surface area up to 1743 m2 g−1 and O, N-enriched structure (O: 25.1%, N: 4.9%). Particularly, the optimized PC-based electrode prepared by using 7% KOH solution showed remarkably high rate capability (89%). This work provides a one-step and cost-effective method to prepare a promising electrode material for high-rate supercapacitors. • PCs were directly obtained from chitosan-based hydrogel beads for only 10 min. • Water acted as microwave absorber and converted into steam as porogen. • KOH simultaneously acted as gelling agent and activating agent. • A remarkably high rate capability of 89% was achieved at 10 A g−1. [ABSTRACT FROM AUTHOR]

Recycling the degraded graphite is becoming increasingly important, which can helped conserve natural resources, reduce waste, and provide economic and environmental benefits. However, current regeneration methods usually suffer from the use of harmful chemicals, high energy and time consumption, and poor scalability. Herein, we report a continuously high‐temperature heating (≈2000 K) process to directly and rapidly upcycle degraded graphite containing impurities. A sloped carbon heater is designed to provide the continuous heating source, which enables robust control over the temperature profile, eliminating thermal barrier for heat transfer compared to conventional furnace heating. The upcycling process can be completed within 0.1 s when the degraded graphite rolls down the sloped heater, allowing us to produce the upcycled graphite on a large scale. High‐temperature heating removes impurities and enhances the graphitization degree and (002) interlayer spacing, making the upcycled graphite more suitable for lithium intercalation and deintercalation. The assembled upcycled graphite||Li cell displays a high reversible capacity of ≈320 mAh g−1 at 1 C with a capacity retention of 96% after 500 cycles, comparable to current state‐of‐the‐art recycled graphite. The method is a chemical‐free, rapid, and scalable way to upcycle degraded graphite, and is adaptable to recycle other electrode materials. [ABSTRACT FROM AUTHOR]

Foam materials are widely used in packaging and buildings for thermal insulation, sound absorption, shock absorption, and other functions. They are dominated by petroleum‐based plastics, most of which, however, are not biodegradable nor fire‐proofing, leading to severe plastic pollution and safety concerns. Here, a fire‐proofing, thermally insulating, recyclable 3D graphite‐cellulose nanofiber (G‐CNF) foam fabricated from resource‐abundant graphite and cellulose is reported. A freeze‐drying‐free and scalable ionic crosslinking method is developed to fabricate Cu2+ ionic crosslinked G‐CNF (Cu‐G‐CNF) foam with a low energy consumption and cost. Moreover, the direct foam formation strategy enables local foam manufacturing to fulfil the local demand. The ionic crosslinked G‐CNF foam demonstrates excellent water stability (the foam can maintain mechanical robustness even in wet state and recover after being dried in air without deformation), fire resistance (41.7 kW m−2 vs 214.3 kW m−2 in the peak value of heat release rate) and a low thermal conductivity (0.05 W/(mK)), without compromising the recyclability, degradability, and mechanical performance of the composite foam. The demonstrated 3D G‐CNF foam can potentially replace the commercial plastic‐based foam materials, representing a sustainable solution against the "white pollution". [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel evaporator is coupled with thermal localization and salt resistant design. • Developed a device to work all weather by photohermal and Joule-heating. • The evaporation rate can reach 10.5 kg m-2h−1 under 0.5 sun and 36 V. • The membrane modules possess excellent molecular sieve effect. • The membrane exhibits excellent anti-bacterial effect and biological safety. Salt blocking and low evaporation efficiency under weak sun irradiation are two obstacles of solar-thermal seawater desalination in the industrialization process. Herein, the challenges are overcome by a solar-thermal interfacial membrane evaporation (STIME) system, i.e., combining merits of advanced thermal management of interfacial evaporation and salt insulation of membrane evaporation, simultaneously achieving salt-resistance, hydrovoltaic generation, and all-weather vapor generation. By employing a hybrid system based on sandwich-like MXene-graphene oxide-MXene (MGM) on a commercial PVDF membrane (MGM@PVDF), we achieved an evaporation efficiency up to 92.5% and without any salt accumulation for 10 h at 10 wt% NaCl solution. Moreover, the system can also be driven by Joule-heating effect for water evaporation under dark or cloudy conditions. The maximum evaporation rate of this system driven by sunlight (0.5 sun) and electricity (36 V) can reach 10.5 kg m-2h−1. Apart from water evaporation, the MGM@PVDF modules possess excellent molecular sieve effect and can pretreat dye pollution before desalination. Furthermore, the MGM@PVDF also exhibits excellent anti-bacterial effect and biocompatibility, ensuring ecological balance during real-world applications. Thus, the developed STIME system provides a novel avenue for all-weather steam generation to constantly provide safe drinking water. [ABSTRACT FROM AUTHOR]

There are significant challenges related to practical applications of superhydrophobic materials due to their limited durability, difficult processing conditions, and complicated synthesis procedures. In this study, a facile and novel emulsion composed of nanopartilcles (i.e. SiO 2 or TiO 2 ) and epoxy resin was synthesized to produce superhydrophobic surfaces using spraying, dipping and brushing methods, mimicking ordinary household paints. The obtained superhydrophobic materials had a water contact angle (CA) of ∼152° and a sliding angle (SA) of ∼6° at the room temperature. Interestingly, the emulsion demonstrated a great versatility for application in type of materials and application methods. The hierarchical surface structure fabricated by the emulsion was found to be independent of the substrate type and processing method, resulting in similar water repellent performance among all surfaces obtained. The superhydrophobic surfaces also exhibited excellent durability even after sustaining a series of mechanical damages including finger wiping, tape peeling and sandpaper abrasion. Moreover, they were able to maintain their superhydrophobic performance after immersion in aqueous solutions of pH ranging from 1 to 13 and boiling in water at 100 °C. This study shows that the novel emulsion can be used to fabrication of superhydrophobic surfaces using a one-step method that is green, versatile, scalable and independent of operator skill, special equipment, and the type of substrate. It has an excellent promise for real life applications. [ABSTRACT FROM AUTHOR]

Biomass-based carbon quantum dots (CQDs) have become a significant carbon materials by their virtues of being cost-effective, easy to fabricate and low in environmental impact. However, there are few reports regarding using cyanobacteria as a carbon source for the synthesis of fluorescent CQDs. In this study, the low-cost biomass of cyanobacteria was used as the sole carbon source to synthesize water-soluble CQDs by a simple hydrothermal method. The synthesized CQDs were mono-dispersed with an average diameter of 2.48 nm and exhibited excitation-dependent emission performance with a quantum yield of 9.24%. Furthermore, the cyanobacteria-derived CQDs had almost no photobleaching under long-time UV irradiation, and exhibited high photostability in the solutions with a wide range of pH and salinity. Since no chemical reagent was involved in the synthesis of CQDs, the as-prepared CQDs were confirmed to have low cytotoxicity for PC12 cells even at a high concentration. Additionally, the CQDs could be efficiently taken up by cells to illuminate the whole cell and create a clear distinction between cytoplasm and nucleus. The combined advantages of green synthesis, cost-effectiveness and low cytotoxicity make synthesized CQDs a significant carbon source and broaden the application of cyanobacteria and provide an economical route to fabricate CQDs on a large scale. [ABSTRACT FROM AUTHOR]