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Highlights: Typical structures/working mechanisms of gel-based triboelectric nanogenerators and performance advantages of gel materials reviewed. Optimization of hydrogels, organogels, and aerogels for triboelectric nanogenerators in flexible sensing summarized. Applications, challenges, and future development directions of gel-based triboelectric nanogenerators in flexible sensing are discussed. The rapid development of the Internet of Things and artificial intelligence technologies has increased the need for wearable, portable, and self-powered flexible sensing devices. Triboelectric nanogenerators (TENGs) based on gel materials (with excellent conductivity, mechanical tunability, environmental adaptability, and biocompatibility) are considered an advanced approach for developing a new generation of flexible sensors. This review comprehensively summarizes the recent advances in gel-based TENGs for flexible sensors, covering their principles, properties, and applications. Based on the development requirements for flexible sensors, the working mechanism of gel-based TENGs and the characteristic advantages of gels are introduced. Design strategies for the performance optimization of hydrogel-, organogel-, and aerogel-based TENGs are systematically summarized. In addition, the applications of gel-based TENGs in human motion sensing, tactile sensing, health monitoring, environmental monitoring, human–machine interaction, and other related fields are summarized. Finally, the challenges of gel-based TENGs for flexible sensing are discussed, and feasible strategies are proposed to guide future research. [ABSTRACT FROM AUTHOR]

Bubble status monitoring is essential for designing material nanostructures and optimizing industrial processes. However, tracking the fluid dynamics of bubbles is challenging due to their random distribution and irregular dynamic changes. In this study, a tube liquid–solid triboelectric nanogenerator serves as a probe to investigate bubbles at the liquid–solid interface. The study explores the impact of bubble fluid dynamics on liquid–solid contact electrification, examining variables such as flow rates, volumes, and release intervals of bubbles. The study demonstrates that the liquid–solid triboelectric probe can work as a non‐intrusive and self‐powered sensor for monitoring bubble states in chemical fluid control. The sensor exhibits a sensitivity of 13.2 V·cm−3, a signal‐bubble volume correlation coefficient of 0.9964, and a rapid response time of 0.15 s. The sensor, integrated with a wireless module, enables continuous remote detection. This work provides a valuable tool for investigating tri‐phase contact electrification dynamics and presents promising technology for bubble state monitoring. [ABSTRACT FROM AUTHOR]

Non‐contact intelligent sensing technology is a key player in the data acquisition and environmental monitoring framework of the Internet of Everything, laying the groundwork for the realization of highly integrated intelligent network systems. However, environmental factors continue to be a major challenge in the process of real‐time monitoring and feedback of objects, constraining the stability and accuracy of the sensing signals. In this study, a hierarchical spatial assembly strategy is implemented to effectively integrate an intermediate energy storage layer with superhydrophobic surfaces (CA = 162 ± 2.5°), resulting in the development of a moisture‐resistant triboelectric structural materials with stable monitoring and tracking capabilities. The moisture‐resistant self‐powered sensor constructed from this triboelectric structural material operates effectively in extreme humidity conditions (99% RH) with a full‐scale output retention rate of 95.2%, and is capable of accurately sensing human activity from the distance of 3 m. Importantly, the sensor can also effectively detect vehicle states during operation and perform real‐time monitoring of the vehicle's surrounding environment. This study not only overcomes the long‐standing challenges of accuracy and stability in high humidity for sensors but also advances the development of sustainable, interconnected intelligent systems for the Internet of Everything in extreme environmental conditions. [ABSTRACT FROM AUTHOR]

Material designs for wearable sensors are increasingly important due to variable application scenarios and environmental disturbances. The high temperatures pose a significant challenge to the performance of sensing materials. The reasonable anisotropic structure in materials is recognized as a promising approach to address this challenge. Precise control of the orientation of the material remains difficult, owing to the entropy effect. In this work, a tunable anisotropic triboelectric aerogel via an in situ coupled magnetic alignment and protonation reduction strategy is demonstrated. The designed orientation with a fitting degree of 98% can effectively suppress electron thermionic emission, which enables the surface charge density to reach 75 µC m−2 at 300 °C. Such a perfect coordination between self‐powered sensing and thermostability innovates multifunctional wearable sensing design at high temperatures, allowing aramid‐based aerogel to be a candidate for advanced sensing materials for applications in the military and aerospace fields. [ABSTRACT FROM AUTHOR]

The rapid development of wearable electronics has placed higher demands on the design strategies of triboelectric materials. Aerogels have the potential to become advanced triboelectric materials, however, traditional design strategies often require complex processes and additional chemical cross‐linking agents to improve the stability of the gel structure, which limits its practical application. In this work, a scalable and sustainable self‐assembly drive strategy is proposed for the design of bio‐based triboelectric aerogels with multi‐scale winding structures. Interestingly, the autoacceleration effect, which is regarded as “unfavorable” during the autocatalytic polymerization of supramolecules, is rationally exploited to provide the supramolecules within the matrix with an abundance of multiple hydrogen bonds at the same time as their rapid gelation occurs. Thanks to this, the aerogel film exhibits ultra‐high tensile strength (104 MPa) and remains undeformed after resisting an impact of 8000 times its own weight. Highly robust triboelectric aerogel films are used to build wearable self‐powered sensors with ultra‐fast response in complex environments (48 ms), while enabling real‐time interaction between the wearer and the information network. The design idea of “ turning a detriment into an asset ” in this work provides a new idea for the material construction of highly robust wearable sensors. [ABSTRACT FROM AUTHOR]

Processing lignin into super-hydrophilic graphite by room-temperature chemical carbonization. [Display omitted] • Room-temperature carbonization has cost-effective and eco-friendly features. • Room-temperature carbonization afforded an 87% graphite yield. • Lignin-derived graphite has super-hydrophilicity. • Graphite-encapsulated liquid metal patterns have superb conductivity of 4.9 × 106 S/m. A cost-effective, and low-energy room-temperature cascade catalytic carbonization strategy is demonstrated for converting lignin into graphite with a high yield of 87 %, a high surface potential of −37 eV and super-hydrophilicity. This super-hydrophilic feature endows the lignin-derived graphite to be dispersed in a variety of polar solvents, which is important for its future applications. Encapsulating of liquid metals with the graphite for electrical circuit patterning on flexible substrates is also advocated. These written patterns show superb conductivity of 4.9 × 106 S/m, offering good performance stability and reliability while being repeatedly stretched, folded, twisted, and bent. This will offer new designs for flexible electronic devices, sensors, and biomedical devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Lithium carboxymethyl cellulose (CMC-Li) is a promising novel water-based binder for lithium-ion batteries. The direct synthesis of CMC-Li was innovatively developed using abundant wood dissolving pulp materials from hardwood (HW) and softwood (SW). The resulting CMC-Li-HW and CMC-Li-SW binders possessed a suitable degree of substitutions and excellent molecular weight distributions with an appropriate quantity of long- and short-chain celluloses, which facilitated the construction of a reinforced concrete-like bonding system. When used as cathode binders in LiFePO 4 batteries, they uniformly coated and dispersed the electrode materials, formed a compact and stable conductive network with high mechanical strength and showed sufficient lithium replenishment. The prepared LiFePO 4 batteries exhibited good mechanical stability, low charge transfer impedance, high initial discharge capacity (∼180 mAh/g), high initial Coulombic efficiency (99 %), excellent cycling performance (<3% loss over 200 cycles) and good rate capability, thereby outperforming CMC-Na and the widely used cathode binder polyvinylidene fluoride. [ABSTRACT FROM AUTHOR]

[Display omitted] • DES improved cellulase activity by mainly rising βG activity with 20–35% increase. • DES improved cellulase stability by compacting the spatial structure. • DES formed a protective layer to prevent unproductive adsorption of lignin on cellulase. • DES significantly increased the saccharification efficiency of corn stover and poplar. The introduction of specific choline chloride (ChCl)- and betaine (Bet)-based deep eutectic solvents (DESs) into the conventional acetic acid–sodium acetate solution led to a significant increase in cellulase activity and stability. In particular, a higher enhancement in β-glucosidase activity was obtained, which plays a key role in improving cellulase function. The DESs prolonged the half-life of cellulase. The addition of 10 % (v/v) ChCl/1,3-propanediol (1:2) and 5 % (v/v) Bet/glycerol (1:2) resulted in the most significant improvement, with the half-life of cellulase reaching three times the initial half-life value. The above both DESs allowed the cellulase to maintain an excellent level of activity over time, even after 72 h. The DESs tightened the structure of the enzyme by changing its secondary structure, which had a stabilizing effect on the overall conformation. The density functional theory calculations of DESs revealed that the DES with a more stable structure more effectively protected the active conformation. The molecular dynamics simulation on β-glucosidase indicated that the hydrogen bond donor end of the DES primarily formed hydrogen bonds with the enzyme, which induced a spatially compact conformation by increasing the α-helix content while reducing the β-sheet content. It also restricted the movement of amino acids, particularly stabilizing the active site, and increased the hydrophilic region, thereby enhancing enzyme activity and stability. In addition, the DES formed a protective layer that prevented the unproductive adsorption of lignin on the enzymes during the hydrolysis of lignocellulosic feedstocks. These multiple improvements provided by DESs significantly increased the enzymatic saccharification efficiency of corn stover and poplar. [ABSTRACT FROM AUTHOR]

Cellulose acetate (CA)-based electrospun nanofiber aerogel (ENA) has drawn extensive attention for wastewater remediation due to its unique separation, inherent porosity and biodegradability. However, the low mechanical strength, poor durability, and limited adsorption ability hinder its further applications. We herein propose using silane-modified ENA, namely T-CA@Si@ZIF-67 (T-ENA), with enhanced resilience, hydrophobicity, durability and hetero-catalysis to remediate a complex wastewater containing oil and drug residues. The robust T-ENA was fabricated by pre-doping tetraethyl orthosilicate (TEOS) and ligand in its spinning precursors, followed by in-situ anchoring of porous ZIF-67 on the electrospun nanofibers (ENFs) via seeding method before freeze-drying and thermal curing (T). Results show that the T-ENA displays enhanced mechanical stability/resilience and hydrophobicity without compromise of its high porosity (>98 %) and low density (10 mg/cm3) due to the silane cross-linking. As a result, the hydrophobic T-ENA shows over 99 % separation efficiency towards different oil-water solutions. Meanwhile, thanks to the enhanced adsorption-catalytic ability and the activation of peroxymonosulfate (PMS) from the porous ZIF-67, fast degradation of carbamazepine (CBZ) residue in the wastewater can be achieved within 20 min. This work might provide a novel strategy for developing CA aerogels to remove organic pollutants. [ABSTRACT FROM AUTHOR]

• TENG significantly improves membrane fouling in ceramic membrane filtration. • A roller-coupled rolling belt TENG with high stability and high electrical output. • The system effectively adjusts the dust migration pattern and morphology. • The system significantly reduces enterprise production costs. Effectively controlling membrane fouling is critically important for enhancing the lifespan of membrane materials and reducing operational costs. This paper introduces a novel approach to control the fouling of gas–solid separation ceramic membranes using a triboelectric negative air ion (NAI) generator. The triboelectric NAI generator mainly consists of a roller-coupled rolling belt triboelectric nanogenerator (RCB-TENG), a boosting circuit, and a NAI emission head module. The RCB-TENG is used to harness the waste kinetic energy in the circular pipeline, and the boosting circuit converts it into high-voltage electrical energy to drive the NAI generator. This study investigated the effects of membrane fouling control, revealing a significant reduction in membrane pressure drop rate by 51.2 % and a decrease in the rate of flux reduction by 78.1 % upon using a triboelectric NAI generator. The backwashing regeneration of the membrane was notably enhanced. The mechanism of membrane fouling control was investigated and it was found that the main control method was through regulating the charge, morphological evolution, and migration characteristics of moving particles. This strengthens the interception and capture on the membrane surface, weakens the inertial collision and diffusion capture effects within the membrane, thereby controlling membrane fouling. This study provides a new perspective for effectively controlling membrane fouling. [ABSTRACT FROM AUTHOR]