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The shrinkage and collapse of wood cell walls during carbonization make it challenging to control the size and shape of carbonized wood (CW) through pre- or postprocessing (e.g., sawing, cutting, and milling). Herein, a shape-adaptive MXene shell (MS) is created on the surface of the wood cell walls. The MS limits the deformation of wood cell walls by spatial confinement and traction effects, which is supported by the inherent dimensional stability of the MS and the formation of new C–O–Ti covalent bonds between the wood cell wall and MS. Consequently, the volumetric shrinkage ratio of CW encapsulated by the MS (CW-MS) is significantly reduced from 54.8% for CW to 2.6% for CW-MS even at 800 °C. The harnessing of this collapse enables the production of CW-MS with prolonged stability and high electric conductivity (384 S m–1). These properties make CW-MS suitable for energy storage devices with various designed shapes, matching the increasingly compact and complex structures of electronic devices.

Twelve ionic liquids were synthesized and used as solvents to extract rose essential oil from rose slag. Tetrabutylammonium bromide propionic acid ionic liquid was selected as the best solvent. Five factors (feed to liquid ratio, extraction temperature, reflux time, stripping agent amount, and repeated extraction times) were considered in the reaction. The results showed that the optimum process conditions were 1:4 mass ratio of material to liquid, the temperature 75 °C, reflux time 4 h, and the amount of stripping agent 100 g; the highest yield of essential oil is 1.6095%. The yield did not show an obvious decline after repeating extraction three times. Comparing the yield, solvent consumption, and extraction time with other organic solvents, using tetrabutylammonium bromide propionic acid ionic liquid can effectively reduce energy and reduce environmental burden, which proves that the technology is sustainable.

The high degree of modularity and miniaturization of nanoelectronic devices results in a significant increase in heat flux per unit area of electronic components. This can cause a rise in temperature, especially when used outdoors under direct sunlight conditions, which can negatively impact their operational stability and service life. Traditional radiators have limited effectiveness in outdoor sunlight conditions. Additionally, conventional heat sinks are often too large and heavy for miniature electronic devices. Therefore, finding an effective solution to cool electronics under sunlight conditions remains a challenge. Herein, we present an innovative solution to fabricate 3D-printed coolers for electronic devices based on the methyltrimethoxysilane/silica/cellulose nanofibers (MSC) ink. 3D printing technology enables the fabrication of radiative coolers with complex structures and efficient cooling performance as needed. The combination of CNFs and SiO₂ nanoparticles, coupled with the porous nature of the structure, enables the 3D-printed MSC scaffold to exhibit excellent solar reflectance and high mid-infrared (MIR) emissivity, thereby facilitating superior radiative cooling capabilities. During the daytime, it can efficiently reduce the temperature of electronic devices by 6.16 °C, thereby improving their operational efficiency and service life. Furthermore, the 3D-printed MSC scaffold exhibits superior mechanical properties due to the robust 3D frame structure formed by the ink components, which provides stability for the electronic device during operation. This study presents an innovative approach to developing electronic device coolers with excellent cooling performance, which is significant in promoting the reliability and stability of electronic devices.

Regulating structural phase transitions of metal insulator transition (MIT) correlated materials is an ideal approach to modulate their properties. However, due to phase transition hysteresis, ultrasensitive electron transition is difficult to achieve. Here, we develop a convenient method via Fe ions surface doping-induced oxygen vacancies (OVs) at the Ti3O5surface to enable ultrasensitive electronic transitions. The Fe doping promotes the formation of free electrons, which is attributed to the reduced bandwidth, making it relatively easy for valence band electrons to leap to the conduction band. The formation of OVs increase the electron concentration and enhance the electronic conductivity (2.49×10−4S/cm) at low temperatures, resulting in an ultrasensitive sensing over a wide temperature range before metal insulator transition. This unique property facilitates its application in fire warning with ultrasensitive sensing (response time 0.63 s, and response temperature 150 °C) and good durability. Moreover, the as-obtained MIT correlated material with rich-OVs structure exhibits excellent oxygen sensing and photothermal conversion properties. These results offer a novel design for MIT correlated materials and provide an innovative insight for modulating their multifunctional properties.

Assembling active materials into dense electrodes is a promising way to obtain high-volumetric-capacitance supercapacitors, but insufficient ion channels in the dense structure lead to a low rate capability. Herein, a dense and robust wood electrode with a large MXene volumetric mass loading (1.25 g cm–3) and abundant ion diffusion channels is designed via a facile capillary-force-driven self-densification strategy. Specifically, MXene is assembled onto a wood cell wall, endowing the wood electrode with good electrical conductivity (86 S cm–1) and high electrochemical activity (5.9 F cm–2at 1 mA cm–2). Notably, the oriented channels along with spaces between adjacent microfibrils recast after densification ensure efficient ion transport for the wood electrode, achieving an excellent rate capability with a high capacitance retention of 77% from 1 to 20 mA cm–2. Meanwhile, the capillary force induces self-densification on the softened wood cell wall, resulting in a highly compact and robust structure for the wood electrode.

Cellulose nanofibers (CNFs) with nanoscale dimension, high aspect ratio, and easily modified surface chemistry show great potential as novel rheological and filtration modifiers in bentonite water-based drilling fluids (BT-WDFs). However, CNFs would suffer from poor redispersibility in an aqueous suspension if they were fully dried for transportation, storage, and field application. Herein, we report a simple, versatile, and scalable strategy to prepare water-redispersible CNFs through compounding them with a water-soluble, commercially available drilling fluid additive, polyanionic cellulose (PAC), and subsequent drying. The results revealed that the water redispersibility of CNF/PAC hybrids was dependent on the PAC’s viscosity (i.e., low viscosity, LV; or regular viscosity, R) as well as drying method (i.e., oven drying, OD; or freeze-drying, FD). Among the obtained CNF/PAC hybrids, the CNF/PAC-R material prepared by FD exhibited optimal water redispersibility due to the enhanced suspending capacity of CNF suspension and the minimized capillary force. As a consequence, the CNF/PAC-R hybrids prepared by FD improved the rheological and filtration performance of BT-WDFs more pronouncedly than others, which could lead to better fluid carrying capacity for drilling cuttings and wellbore stability. The PAC acted not only as water-dispersible agents for CNFs but also as additives for modifying the rheological and filtration properties of BT-WDFs. PAC-coated cellulose nanofibers can be used as water-redispersible dry additive for drilling fluids with enhanced fluid performance.

Thermal insulation aerogel holds great promise in the transportation, storage, and use of temperature-sensitive electronic components under different environmental conditions. Due to their low density, high thermal stability, superior UV resistance, and low thermal conductivity, lignocellulose nanofibrils (LCNFs) aerogels meet the thermal insulation needs perfectly. However, the preparation of LCNFs aerogels with customizable size and high precision remains challenging. Herein, we report the following: (1) the preparation of LCNFs with tunable physicochemical properties from unbleached poplar pulp through the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation and ultrasonication approach, and (2) the 3D printing of customized thermal insulation materials using LCNFs as viscoelastic gelatinous inks. In addition to the chlorine-free bleaching merit, the LCNF inks exhibit much lower yield stress compared to cellulose nanofibrils (CNFs) inks, thereby facilitating the smooth extrusion of filament under a much lower printing pressure. Furthermore, the residual lignin endows LCNFs aerogels with superior moisture tolerance, mechanical protection, UV resistance, and thermal insulation performance for temperature sensitive electronic components such as chips and batteries. This work opens a promising avenue for the rapid manufacturing of customizable thermal insulation materials in a sustainable, cost-effective, and eco-friendly manner.

An electrolyte additive, with convenient operation and remarkable functions, has been regarded as an effective strategy for prolonging the cycle life of aqueous zinc ion batteries. However, it is still difficult to dynamically regulate the unstable Zn interface during long-term cycling. Herein, tricine was introduced as an efficient regulator to achieve a pH-stable and byproduct-free interface. The functional zwitterion of tricine not only inhibits interfacial pH perturbation and parasitic reactions by the trapping effect of an anionic group (-COO–) but also simultaneously creates a uniform electric field by the electrostatic shielding effect of a cationic group (-NH2+). Such synergy accordingly eliminates dendrite formation and creates a chemical equilibrium in the electrolyte, endowing the Zn||Zn cell with long-term Zn plating/stripping for 2060 h at 5 mA cm–2and 720 h at 10 mA cm–2. As a result, the Zn||VS2full cell under a high cathodic loading mass (8.6 mg cm–2) exhibits exceptional capacity retention of 93% after 1000 cycles.

Zinc metal batteries are strongly hindered by water corrosion, as solvated zinc ions would bring the active water molecules to the electrode/electrolyte interface constantly. Herein, we report a sacrificial solvation shell to repel active water molecules from the electrode/electrolyte interface and assist in forming a fluoride-rich, organic–inorganic gradient solid electrolyte interface (SEI) layer. The simultaneous sacrificial process of methanol and Zn(CF3SO3)2results in the gradient SEI layer with an organic-rich surface (CH2OC– and C5product) and an inorganic-rich (ZnF2) bottom, which combines the merits of fast ion diffusion and high flexibility. As a result, the methanol additive enables corrosion-free zinc stripping/plating on copper foils for 300 cycles with an average coulombic efficiency of 99.5%, a record high cumulative plating capacity of 10 A h/cm2at 40 mA/cm2in Zn/Zn symmetrical batteries. More importantly, at an ultralow N/P ratio of 2, the practical VO2//20 μm thick Zn plate full batteries with a high areal capacity of 4.7 mAh/cm2stably operate for over 250 cycles, establishing their promising application for grid-scale energy storage devices. Furthermore, directly utilizing the 20 μm thick Zn for the commercial-level areal capacity (4.7 mAh/cm2) full zinc battery in our work would simplify the manufacturing process and boost the development of the commercial zinc battery for stationary storage.

The development of porous three-dimensional (3D) monoliths from natural materials for a wide spectrum of thermal insulation, energy storage and tissue engineering applications has recently gained tremendous interest. However, the lack of 3D structural customization and shape fidelity of monoliths limited their effectiveness in meeting a variety of practical uses. Herein, the material extrusion-based 3D printing technology is used to manufacture a variety of 3D customized monoliths with high shape fidelity that are useful for thermal insulation and energy storage applications. By using sustainable wood-derived cellulose nanofiber (CNF) gels as inks, the 3D printability and shape fidelity are systematically optimized by tailoring the concentration-dependent rheological properties as well as the printing parameters. Benefitted from the high fidelity and self-supporting features, the optimized 3D printed CNF monoliths can be further transformed into porous CNF scaffolds with highly-retained 3D shape using a well-established freeze-drying technique without the use of any specific container. The as-prepared CNF scaffold has porous structure, superior mechanical properties, and low thermal conductivity, demonstrating well heat insulation properties. Furthermore, the porous CNF scaffold can be used as a platform for the in-situ polymerization of aniline (ANi). The resultant CNF-PANi scaffold has a conductivity of 0.334 S•cm−1, and delivers a high capacitance of 107.9 mF·cm−2(@0.2 mA·cm−2) as a binder-free electrode in supercapacitors. This work provides some guidance for 3D printing of customizable monoliths from sustainable materials by tuning the rheological properties and printing parameters for thermal insulation and energy storage applications.