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ABSTRACT Atmospheric water harvesting (AWH) is a promising strategy to alleviate freshwater scarcity, with hygroscopic salts (e.g., LiCl) widely employed as active sorbents due to their high water affinity. However, practical deployment is hindered by the deliquescence of salts, which can lead to leakage, migration, and potential corrosion. Herein, we report a robust LiCl+CMC@cellulose composite foam fabricated via a scalable room‐temperature impregnation–drying strategy. By introducing carboxymethyl cellulose (CMC) as a polymeric stabilizer, we effectively immobilize LiCl within the cellulose scaffold through ionic coordination, suppressing salt aggregation and leakage. Benefiting from the hierarchical porous architecture of cellulose and this salt immobilization strategy, the optimized composite (treated by 15 wt% LiCl, 0.5 wt% CMC solution) achieves a high water uptake of 3.57 ± 0.15 g at 25°C and 90% relative humidity (RH) within 24 h, corresponding to 16.04± 0.82 g g⁻¹when normalized to pristine cellulose foam, representing a 15.4% enhancement over non‐stabilized counterparts. Crucially, the composite exhibits excellent durability, retaining 82.4% of its capacity after ten water uptake–release cycles. Furthermore, a spray‐coated carbon black (CB) surface layer enables rapid photothermal heating (up to 50.6°C under one sun irradiation), facilitating efficient solar‐driven water release. This integrated, environmentally benign design offers a low‐cost, durable platform for scalable, high‐performance AWH. 

Abstract Multifunctional fibers with high mechanical strength enable advanced applications of smart textiles, robotics, and biomedicine. Herein, we reported a one-step degumming method to fabricate strong, stiff, and humidity-responsive smart cellulosic fibers from abundant natural grass. The facile process involves partially removing lignin and hemicellulose functioning as glue in grass, which leads to the separation of vessels, parenchymal cells, and cellulosic fibers, where cellulosic fibers is manufactured at kilogram scale. The resulting fibers show dense and unidirectional fibril structure at both micro- and nano-scales, which demonstrate high tensile strength of ∼0.9 GPa and Young's modulus of 72 GPa, being 13- and 14-times higher than original grass. Inspired by stretchable plant tendrils, we developed humidity-responsive actuator by engineering cellulosic fibers into spring-like structure, presenting superior response rate and lifting capability. These strong and smart cellulosic fibers can be manufactured at large scale with low cost, representing promising fiber material derived from renewable and sustainable biomass. 

Abstract One possible solution against the accumulation of petrochemical plastics in natural environments is to develop biodegradable plastic substitutes using natural components. However, discovering all-natural alternatives that meet specific properties, such as optical transparency, fire retardancy and mechanical resilience, which have made petrochemical plastics successful, remains challenging. Current approaches still rely on iterative optimization experiments. Here we show an integrated workflow that combines robotics and machine learning to accelerate the discovery of all-natural plastic substitutes with programmable optical, thermal and mechanical properties. First, an automated pipetting robot is commanded to prepare 286 nanocomposite films with various properties to train a support-vector machine classifier. Next, through 14 active learning loops with data augmentation, 135 all-natural nanocomposites are fabricated stagewise, establishing an artificial neural network prediction model. We demonstrate that the prediction model can conduct a two-way design task: (1) predicting the physicochemical properties of an all-natural nanocomposite from its composition and (2) automating the inverse design of biodegradable plastic substitutes that fulfils various user-specific requirements. By harnessing the model’s prediction capabilities, we prepare several all-natural substitutes, that could replace non-biodegradable counterparts as exhibiting analogous properties. Our methodology integrates robot-assisted experiments, machine intelligence and simulation tools to accelerate the discovery and design of eco-friendly plastic substitutes starting from building blocks taken from the generally-recognized-as-safe database. 

Abstract Cellulose nanofibers (NFCs) have emerged as a preferred choice for fabricating nanomaterials with exceptional mechanical properties. At the same time, boron nitride nanotubes (BNNTs) have long been favored in thermal management devices due to their superior thermal conductivity (k). This study uses reverse non-equilibrium molecular dynamics (MD) simulations to investigatekfor a hybrid material based on NFCs and BNNTs. The result is then compared with pure NFC and BNNT-based structures with equivalent total weight content to elucidate how incorporating BNNT fillers enhanceskfor the hybrid system. Furthermore, the fundamental phonon vibration modes responsible for driving thermal transport in NFC-based materials upon incorporating BNNTS are identified by computing the vibrational density of states from the Fourier transform analysis of the averaged mass-weighted velocity autocorrelation function. Additionally, MD simulations demonstrate how both NFCs and BNNTs synergistically improve the constituting hybrid structure’s mechanical properties (e.g. tensile strength and stiffness). The overarching aim is to contribute towards the engineered design of novel functional materials based on nanocellulose that simultaneously improve crucial physical properties pertaining to thermal transport and mechanics. 

This study presents a facile strategy for fabricating chitosan/polyurethane nanoparticle (PU NP) bioplastic films that simultaneously enhance both ductility and strength due to their unique elastic node-grid structure. 

Abstract 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 Cu 2+ 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”. 

Hydrogels showing strong adhesion to different substrates have garnered significant attention for engineering applications. However, the current development of such hydrogel-based adhesive is predominantly limited to synthetic polymers, owing to their exceptional performance and an extensive array of chemical options. To advance the development of sustainable hydrogel-based adhesives, we successfully create a highly robust all-cellulose hydrogel-based adhesive, which is composed of concentrated dialcohol cellulose nanorods (DCNRs) and relies on enhanced hydrogen bonding interactions between cellulose and the substrate. We implement a sequential oxidization-reduction process to achieve this high-performance all-cellulose hydrogel, which is realized by converting the two secondary hydroxyl groups within an anhydroglucose unit into two primary hydroxyl groups, while simultaneously linearizing the cellulose chains. Such structural and chemical modifications on cellulose chains increase out-of-plane interactions between the DCNRs hydrogel and substrate, as simulations indicate. Additionally, these modifications enhance the flexibility of the cellulose chains, which would otherwise be rigid. The resulting all-cellulose hydrogels demonstrate injectability and strong adhesion capability to a wide range of substrates, including wood, metal, glass, and plastic. This green and sustainable all-cellulose hydrogel-based adhesive holds great promise for future bio-based adhesive design. 

Conventional strategies for materials design have long been used by leveraging primary bonding, such as covalent, ionic, and metallic bonds, between constituent atoms. However, bond energy required to break primary bonds is high. Therefore, high temperatures and enormous energy consumption are often required in processing and manufacturing such materials. On the contrary, intermolecular bonds (hydrogen bonds, van der Waals forces, electrostatic interactions, imine bonds, etc.) formed between different molecules and functional groups are relatively weaker than primary bonds. They, thus, require less energy to break and reform. Moreover, intermolecular bonds can form at considerably longer bond lengths between two groups with no constraint on a specific bond angle between them, a feature that primary bonds lack. These features motivate unconventional strategies for the material design by tuning the intermolecular bonding between constituent atoms or groups to achieve superior physical properties. This paper reviews recent development in such strategies that utilize intermolecular bonding and analyzes how such design strategies lead to enhanced thermal stability and mechanical properties of the resulting materials. The applications of the materials designed and fabricated by tuning the intermolecular bonding are also summarized, along with major challenges that remain and future perspectives that call for further attention to maximize the potential of programming material properties by tuning intermolecular bonding.