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Water-soluble silver nanoclusters (AgNCs) as a new type of fluorescent material have attracted much attention for their remarkable optical properties and excellent cytocompatibility. However, it is still challenging to synthesize water-soluble AgNCs with good cytocompatibility and excellent fluorescence. Herein, the dialdehyde nanofibrillated cellulose (DANFC)- reduced water-soluble AgNCs capped by glutathione (GSH) with tunable fluorescence emissions were first reported. The DANFC provides a mild reduction environment and crystal growth system for the coordination between silver ions and GSH compared to conventional methods using strong reducing agents. The AgNCs with intense red fluorescence (R-AgNCs@GSH, size ∼2.24 nm) and green fluorescence (G-AgNCs@GSH, size ∼1.93 nm) were produced by varying the ratios of silver sources and ligands, and could maintain stable fluorescence intensity over 6 months. Moreover, the CCK-8 study demonstrated that the R-AgNCs@GSH and G-AgNCs@GSH reduced by DANFC of excellent cytocompatibility (cell viability >90 %) and enable precise multicolor intracellular imaging of Hela cells in 1 h. This work proposes a novel method to synthesize water-soluble AgNCs with tunable fluorescence emission at room temperature based on the classical silver- mirror reaction (SMR) using DANFC as reducing agent, and the synthesized fluorescent AgNCs have great potential as novel luminescent nanomaterials in biological research., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Chloropropanols are among the major food contaminants, and quantifying their content in food is a key food-safety issue. In response to the demand for highly sensitive and selective analysis, the scientific community is committed to continuous innovation and optimization of various analytical techniques. This paper comprehensively reviews the latest developments in chloropropanol analysis technologies and systematically compares and analyzes the working principles, application conditions, advantages, and challenges of these methods. Gas chromatography-mass spectrometry is the preferred choice for chloropropanol analysis in complex sample matrices owing to its high resolution, sensitivity, and accuracy. Electrochemical methods provide strong support for the real-time monitoring of chloropropanols because of their high selectivity and sensitivity towards electrochemically active molecules. Other techniques offer innovative solutions for the rapid and accurate analysis of chloropropanol at different levels. Finally, innovative directions for the development of chloropropanol analysis methods for food safety are highlighted., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Pulp and paper are gradually transforming from a traditional industry into a new green strategic industry. In parallel, cellulose-derived transparent paper is gaining ground for the development of advanced functional materials for light management with eco-friendly, high performance, and multifunctionality. This review focuses on methods and processes for the preparation of cellulose-derived transparent papers, highlighting the characterization of raw materials linked to responses to different properties, such as optical and mechanical properties. The applications in electronic devices, energy conversion and storage, and eco-friendly packaging are also highlighted with the objective to showcase the untapped potential of cellulose-derived transparent paper, challenging the prevailing notion that paper is merely a daily life product. Finally, the challenges and propose future directions for the development of cellulose-derived transparent paper are identified., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Sunflower oil (SFO) and Flaxseed oil (FSO) were microencapsulated using simple and complex coacervation techniques with Opuntia (Cactaceae) mucilage (Mu) and with a combination of Mu with chitosan (Chit). The encapsulation efficiency (EE) of SFO and FSO in emulsions using Mu/Chit shells was 96.7% and 97.4%, respectively. Morphological studies indicated successful entrapment of oils in core shells with particle sizes ranging from 1396 ± 42.4 to 399.8 ± 42.3 nm. The thermogravimetric analyses demonstrated enhanced core protection with thermal stability noted for microcapsules regardless of encapsulation method. The stability of the microcapsules, during in vitro digestion was studied. The obtained results revealed that the microcapsules are intact in oral conditions and have a slow release of oil over stomach digestion and rapid release in the small intestine. The results showed that Mu and Mu/Chit coacervates can be used as effective carrier systems to encapsulate sensitive ingredients and functional oils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The traditional starch-based intelligent freshness labels struggle to maintain long-term structural stability when exposed to moisture. To solve this problem, we prepared composite crosslinked labels using phytic acid for double crosslinking of corn starch and soybean isolate proteins, with anthocyanin serving as the chromogenic dye. The mechanical properties, hydrophobic characteristics, and pH responsivity of these crosslinked labels were assessed in this study. The prepared double-crosslinked labels showed reduced moisture content (15.96%), diminished swelling (147.21%), decreased solubility (28.55%), and minimized water permeability, which suggested that they have enhanced hydrophobicity and densification. The crosslinked labels demonstrated the ability to maintain morphological stability when immersed in water for 12 h. Additionally, the mechanical properties of the crosslinked labels were enhanced without compromising their pH-sensing capabilities, demonstrated a color response visible to the naked eye for milk and coconut water freshness monitoring, suggesting great potential for application in beverages freshness monitoring., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Recently, fiber-based and functional paper food packaging has garnered significant attention for its versatility, excellent performance, and potential to provide sustainable solutions to the food packaging industry. Fiber-based food packaging is characterized by its large surface area, adjustable porosity and customizability, while functional paper-based food packaging typically exhibits good mechanical strength and barrier properties. This review summarizes the latest research progress on food packaging based on fibers and functional paper. Firstly, the raw materials used for preparing fiber and functional paper, along with their physical and chemical properties and roles in food packaging, were discussed. Subsequently, the latest advancements in the application of fiber and paper materials in food packaging were introduced. This paper also discusses future research directions and potential areas for improvement in fiber and functional paper food packaging to further enhance their effectiveness in ensuring food safety, quality, and sustainability., Competing Interests: Declaration of competing interest The authors declare they have no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Flexible conductive hydrogels (FCHs) have attracted widespread interest as versatile monoliths that can be intricately integrated with various ingredients boasting multiple functionalities. The chemicophysical properties of FCHs cover a wide range, which significantly vary in their building blocks. However, achieving both favorable mechanical strength and high conductivity simultaneously through a facile approach remains a challenge. Herein, polyvinyl alcohol, dialdehyde cellulose nanofibrils, silver nanoparticles, borax, and tannic acid are readily "one-pot" incorporated into FCHs with great tensile stress (499 kPa), tensile strain (4591 %), and compressive stress (269 kPa) due to abundant hydrogen bonding, dynamic borate-diol bonding, and intermolecular acetalization. They also exhibit desired self-healing, generalized-adhesive, and antibacterial performances. Taking advantage of these, FCHs are further employed to support an epidermal sensor, on which remarkable strain sensitivity (gauge factor = 8.22), high-pressure sensitivity (≥ 0.258 kPa -1 ), and fast response (≤ 190 ms) are recorded. Its highly adaptive mechano-electric transformability and functions can be well maintained in serving as an array unit and touch screen pen. The results well addressed in this work are anticipated to pave the universal way of engineering FCHs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Cryogels that are constructed with cellulose nanofibrils (CNF) are important as green materials for a wide range of applications. However, their utilization is limited by inherent hydrophilicity and insufficient mechanical properties. Herein, a processable CNF/nanochitin (NCh)-stabilized Pickering emulsion that contains polylactide (PLA) in the oil phase is developed to directly produce ternary composite cryogels via freeze-drying. The complexation of CNF with NCh promotes CNF adsorption at the surface of PLA droplets, resulting in formation of uniform Pickering PLA droplets. The CNF/NCh complex-stabilized PLA droplets are easy to be translated to the internal structure of the cryogels, exhibiting lightweight nature and possessing highly porous structure. The interconnected network and lamellar structure formed by the CNF/NCh complexes, associating with inclusion of PLA particles, improve the cryogel structure integrity upon post-processing and endow hydrophilic cryogel with water resistance. This study offers a straightforward and eco-friendly Pickering emulsion template on fabrication of the CNF-based composite cryogel with controllable microstructure and mechanical performance, broadening construction of nanocellulose-based composites., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The development of highly effective chitosan-based hemostatic materials that can be utilized for deep wound hemostasis remains a considerable challenge. In this study, a hemostatic antibacterial chitosan/N-hydroxyethyl acrylamide (NHEMAA)/Ti 3 C 2 T x (CSNT) composite cryogel was facilely prepared through the physical interactions between the three components and the spontaneous condensation of NHEMAA. Because of the formation of strong crosslinked network, the CSNT cryogel showed a developed pore structure (~ 99.07 %) and superfast water/blood-triggered shape recovery, enabling it to fill the wound after contacting the blood. Its capillary effect, amino groups, negative charges, and affinity with lipid collectively induced rapid hemostasis, which was confirmed by in vitro and in vivo analysis. In addition, CSNT cryogel showed excellent photothermal antibacterial activities, high biosafety, and in vivo wound healing ability. Furthermore, the presence of chitosan effectively prevented the oxidation of MXene, thus enabling the long-term storage of the MXene-reinforced cryogel. Thus, our hemostatic cryogel demonstrates promising potential for clinical application and commercialization, as it combines high resilience, rapid hemostasis, efficient sterilization, long-term storage, and easy mass production., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Properties of cellulose are typically functionalized by organic chemistry means. We progress an alternative facile way to functionalize cellulose by functional group counter-cation exchange. While ion-exchange is established for cellulose, it is far from exploited and understood beyond the most common cation, sodium. We build on our work that established the cation exchange for go-to alkali metal cations. We expand and further demonstrate the introduction of functional cations, namely, lanthanides. We show that cellulose nanocrystals (CNCs) carrying sulfate-half ester groups can acquire properties through the counter-cation exchange. Trivalent lanthanide cations europium (Eu 3+ ), dysprosium (Dy 3+ ) and gadolinium (Gd 3+ ) were employed. The respective ions showed distinct differences in their ability of being coordinated by the sulfate groups; with Eu 3+ fully saturating the sulfate groups while for Gd 3+ and Dy 3+ , values of 82 and 41 % were determined by compositional analysis. CNCs functionalized with Eu 3+ displayed red emission, those containing Dy 3+ exhibited no optical functionality, while those with Gd 3+ revealed significantly altered magnetic relaxation times. Using cation exchange to alter cellulose properties in various ways is a tremendous opportunity for modification of the abundant cellulose raw materials for a renewable future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Widely employed petroleum-based food packaging materials have inflicted irreparable harm on ecosystems, primarily stemming from their non-biodegradable attributes and recycling complexities. Inspired by natural nacre with a layered aragonite platelet/nanofiber/protein multi-structure, we prepared high-barrier composite films by self-assembly of cellulose nanofibrils (CNF), cellulose nanocrystals (CNC), montmorillonite (MMT), polyvinyl alcohol (PVA) and alkyl ketene dimer (AKD). The composite films demonstrated outstanding barrier properties with oxygen vapor transmission of 0.193 g·mm·m -2 ·day -1 and water vapor transmission rates of 0.062 cm 3 ·mm·m -2 ·day -1 ·0.1 MPa -1 , which were significantly lower than those of most biomass-degradable packaging materials. Additionally, the impacts of mixing nanocellulose with various aspect ratios on the tensile strength and folding cycles of the films were examined. The exceptional resistance of the composite films to oil and water provides a novel and sustainable approach to reduce non-biodegradable plastic packaging., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The colored and high-saline effluents during the traditional dyeing process poses serious environmental challenge. In our study, an eco-friendly cationic cellulose nano-fiber/chitosan (CCNF/CS) binary versatile auxiliary was designed for the neutral salt-free dyeing and physical enhancement of paper by mixing with pulp simply. Profiting from the rich cationic binding sites of CCNF/CS (Charge density: 3749.67 μmol/g), under near neutral conditions (pH = 6.2), the maximum adsorption capacity of anionic GL (Direct fast turquoise blue GL) on paper with 0.5 % CCNF/CS reached 1865.06 mg/g with a desirable evenness (45.5 % and 92.1 % higher than that of CCNF and NaCl group, respectively), and the dye uptake was up to 97 %. The spontaneous adsorption behavior was aligned with the pseudo-second-order and Langmuir models, with a primary physical mechanism enhanced by chemical forces. The combination of strong electronic attraction, hydrogen bonding, and n-π stacking effects granted CCNF/CS an enhanced proficiency in anionic dye adsorption. In addition, the tensile strength of the resulting paper yarn with 0.5 % CCNF/CS increased to 52.47 MPa under the optimal parameters, deriving from the CCNF/CS-induced inter-fiber cohesion. Overall, our research provided a green promising approach for the innovative neutral salt-free dyeing and mechanical enhancement of paper., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

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/cm 3 ) 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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In this study, the quaternized carboxymethyl chitosan (QCMCS), oxidized hyaluronic acid (OHA), 3,3'-dithiobis-(propionohydrazide) (DTP) were used as raw materials for the synthesis of hydrogels with excellent properties as carriers for drug release. The hydrogels were prepared by a simple "one-pot" method without external stimuli on the basis of interactions between formed dynamic covalent bonds (imine bonds, acylhydrazone bonds, disulfide bonds) and hydrogen bonds. The hydrogels had rapid self-healing properties, with a self-healing rate of 96 % after 30 min, as well as good pH responsiveness and excellent cytocompatibility (up to 98 % cell survival). The compressive stress of the hydrogels reached 423 kPa. Moreover, a representative drug (acetylsalicylic acid) demonstrated sustained release in the hydrogels (>72 h). The drug release behaviour was shown to be consistent with the Fick diffusion mechanism by kinetic modelling. Collectively, the findings demonstrate that the QCMCS + OHA + DTP injectable self-healing hydrogels are a potential material for the construction of pH-controlled drug delivery platforms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Deep eutectic solvents (DES) have been regarded as green solvents in the biorefinery of lignocellulosic biomass, but long duration time has severely limited efficiency. The microwave-assisted DES pretreatment along with enzymatic hydrolysis and high-pressure homogenization process was proposed to produce lignin-containing cellulose nanofibrils (LCNF) from corncob. Benefiting from microwave-assisted DES pretreatment, the duration time was greatly shortened; meanwhile the effects of different kinds of DES on the resultant LCNF were investigated. The results showed that, the microwave-assisted DES fabricated LCNF (M-LCNF) was successfully obtained, exhibiting good nano size, thermal stability, colloidal stability, and fluorescence. M-LCNF was further introduced into phytic acid (PA) enhanced poly(acrylamide-co-acrylic acid) (P(AM-co-AA)) network and constructed composite conductive hydrogels (PLP). The obtained hydrogels exhibited good mechanical strength, UV blocking ability, fluorescence, and conductivity. A simple battery assembled with the resultant PLP as electrolyte had an out voltage of 2.41 V. The composite conductive hydrogel showed good sensing performance towards different stimuli (e.g., stretching and compression) and human motions in real time. It is expected that this research would provide an alternative way for green fabrication of LCNF and potential application of LCNF in flexible sensors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Nanocellulose films possess numerous merits ascribing to their inherent biocompatibility, non-toxic and biodegradability properties. The potential for practical applications would be improved if their mechanical strength and toughness requirements could be met simultaneously. Herein, dual cross-linked nanocellulose (DC) film was fabricated by the treatments of chemical and physical cross-linking, which was mechanically superior to pure nanocellulose (CNF) films. To further increase the toughness of DC films, spherical cellulose (Sph) was incorporated into DC film (DC-Sph film), and analyzed under different humidity conditions (RH) (from 10 % to 90 %). The changes of functional groups of CNF, DC and DC-Sph films were detected by FTIR and XPS spectrum. The epichlorohydrin and Sph content were optimized, followed by the investigation of RH on the toughness of films. The highest tensile strength (146.6 ± 4.6 MPa) was obtained in DC film at 50 % RH, while the DC-Sph film showed the largest toughness (40.3 ± 3.7 kJ/m 2 ) at 70 % RH. Furthermore, the possible toughening mechanism of DC-Sph film was also discussed., Competing Interests: Declaration of competing interest There is no conflict of interest., (Copyright © 2023. Published by Elsevier Ltd.)

Foams with advanced sensing properties and excellent mechanical properties are promising candidates for smart packaging materials. However, the fabrication of ultra-elastic and durable foams is still challenging. Herein, we report a universal strategy to obtain ultra-elastic and durable foams by crosslinking cellulose nanofiber and MXene via strong covalent bonds and assembling the composites into anisotropic cellular structures. The obtained composite foam shows an excellent compressive strain of up to 90 % with height retention of 97.1 % and retains around 90.3 % of its original height even after 100,000 compressive cycles at 80 % strain. Their cushioning properties were systematically investigated, which are superior to that of wildly-used petroleum-based expanded polyethylene and expanded polystyrene. By employing the foam in a piezoelectric sensor, a smart cushioning packaging and pressure monitoring system is constructed to protect inner precision cargo and detect endured pressure during transportation for the first time., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

In this work, saccharide branched cellulose (saccharide b-Cel) was synthesized by combining reducing saccharides with cellulose molecules using Ugi four-component reaction (Ugi-4CR). First, the carboxyl groups required for Ugi-4CR are obtained by carboxymethylating cellulose molecules. Then, saccharide b-Cel with a controlled molecular structure is formed when the terminal aldehyde group of reducing saccharides combines with the carboxyl group and auxiliary functional group. The types of saccharides, the degree of substitution of carboxymethyl groups, and the degree of branching all affect the molecular structure of saccharide b-Cel. Through molecular structural regulation, the relationship between the branching structure and water retention ability of saccharide b-Cel was examined in detail. This work not only provides new insights into the synthesis of cellulose derivatives, but it also provides a template for the synthesis of other biomass derivatives., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Simultaneously having competitive compressive properties, fatigue-resistant stability, excellent conductivity and sensitivity has still remained a challenge for acrylic-based conductive hydrogels, which is critical in their use in the sensor areas where pressure is performed. In this work, an integrated strategy was proposed for preparing a conductive hydrogel based on acrylic acid (AA) and sodium alginate (SA) by addition of carboxylic-cellulose nanocrystals (CNC-COOH) followed by metal ion interaction to reinforce its compressive strength and conductivity simultaneously. The CNC-COOH played a multifunctional role in the hydrogel by well-dispersing SA and AA in the hydrogel precursor solution for forming a uniform semi-interpenetrating network, providing more hydrogen bonds with SA and AA, more -COOH for metal ion interactions to form uniform multi-network, and also offering high modulus to the final hydrogel. Accordingly, the as-prepared hydrogels showed simultaneous excellent compressive strength (up to 3.02 MPa at a strain of 70 %) and electrical conductivity (6.25 S m -1 ), good compressive fatigue-resistant (93.2 % strength retention after 1000 compressive cycles under 50 % strain) and high sensitivity (gauge factor up to 14.75). The hydrogel strain sensor designed in this work is capable of detecting human body movement of pressing, stretching and bending with highly sensitive conductive signals, which endows it great potential for multi-scenario strain sensing applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Achieving excellent ultraviolet (UV) blocking properties and maintaining high light transmittance are highly challenging. In this study, a facile and green polymer-assisted vacuum filtration strategy was used to prepare cellulose nanocrystal (CNC) one-dimensional photonic crystal (1DPhC) films with excellent UV-blocking performance and good transparency. The polymer-assisted self-assembly behaviors of CNC and the hydrogen bonding interaction between CNC, polyethylene glycol (PEG), and graphene oxide (GO) drive the homogeneous distribution and parallel alignment of GO. The UV absorption of GO and high reflection of UV resulting from the chiral nematic structure of CNCs result in excellent UV-blocking and high visible light transmission. Besides, the strong hydrogen bonding interaction among CNC, PEG, and GO endows the films with obviously increased mechanical properties. The UV-blocking and the transparency of the CNC composite films could reach 98.3 % and 60.5 %, respectively. Besides, the strain at break of the composite film reached 1.72 ± 0.11 %, which was 535.94 % of neat CNC films. The CNC composite films present great potential in the field of UV-blocking glass, sensors, anti-counterfeiting measures, radiation protection, and so on., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The increasing commercialization of flexible electronic products has sparked a rising interest in flexible wearable energy storage devices. Supercapacitors are positioned as one of the systems with the most potential due to their distinctive advantages: high power density, rapid charge and discharge rates, and long cycle life. However, electrode materials face challenges in providing excellent mechanical strength while ensuring sufficient energy density. This study presents a method for constructing a flexible composite electrode material with high capacitance and mechanical performance by electrochemically depositing high-quality manganese dioxide (MnO 2 ) onto the surface of a nanocellulose (CNF) and carbon nanotube (CNT) conductive film. In this electrode material, the CNF/CNT composite film serves as a flexible conductive substrate, offering excellent mechanical properties (modulus of 3.3 GPa), conductivity (55 S/cm), and numerous active sites. Furthermore, at the interface between MnO 2 and the CNF/CNT substrate, C-O-Mn bonds are formed, promoting a tight connection between the composite materials. The assembled symmetric flexible supercapacitor (FSC) demonstrates impressive performance, with an areal specific capacitance of 934 mF/cm 2 , an energy density of 43.10 Wh/kg, a power density of 166.67 W/kg and a long cycle life (85 % Capacitance retention after 10,000 cycles), suggesting that they hold promise for FSC applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Liquid penetration in porous cellulosic materials is crucial in many technological fields. The complex geometry, small pore size, and often fast timescale of liquid uptake makes the process hard to capture. Effects such as swelling, vapor transport, film flow and water transport within cellulosic material makes transport deviate from well-known relations such as Lucas-Washburn and Darcy's Law. In this work it is demonstrated how Ultra-Fast Imaging NMR can be used to simultaneously monitor the liquid distribution and swelling during capillary uptake of water with a temporal- and spatial resolution of 10 ms and 14.5-18 μm respectively. The measurements show that in a cellulose fiber sheet, within the first 65 ms, liquid first penetrates the whole sheet before swelling takes place for another 30 s. Furthermore, it was observed that the liquid front traps 15 v% of air which is slowly replaced by water during the final stage of liquid uptake. Our method makes it possible to simultaneously quantify the concentration of all three phases (solid, liquid and air) within porous materials during processes exceeding 50 ms (5 times the temporal resolution). We hence believe that the proposed method should also be useful to study liquid penetration, or water diffusion, into other porous cellulosic materials like foams, membranes, nonwovens, textiles and films., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Herein, we propose a carbon/TiO 2 /Co 3 O 4 (CTC) composite carbon aerogel with a 3D porous conductive network structure derived from sodium carboxymethylcellulose (CMC)/Mxene (Ti 3 C 2 T x )/zeolite imidazolium framework-67 (ZIF-67). Among them, CMC is used as the carbon skeleton, which can reduce the powdering caused by volume change and improve the cycle stability. Ti 3 C 2 T x acts as the conductive agent and dispersant for ZIF-67, exposing more reactive sites while constructing fast conductive channels to enhance electrochemical performance. The microstructure of the CTC carbon aerogel is modulated by controlling the mass ratio of Ti 3 C 2 T x to ZIF-67, and the carbon aerogel with a mass ratio of 2:3 (CTC-2:3) is experimentally demonstrated to have the best electrochemical performance. The CTC-2:3 electrode exhibits a high specific capacitance of 481.7 F g -1 at 1 A g -1 and possesses a rate performance of 78.9 % at 10 A g -1 . The assembled asymmetric supercapacitor (ASC, CTC-2:3//Ti 3 C 2 T x ) delivers an energy density of 48.4 Wh kg -1 at a power density of 699.8 W kg -1 . Moreover, the ASC device maintains 85.3 % initial capacitance and 99.1 % coulombic efficiency after 10,000 GCD cycles, indicating good cycling stability. This facile design pathway provides a new insight for the development of high-performance electrode materials., Competing Interests: Declaration of competing interest No conflict of interest exits in the submission of this manuscript, and the manuscript is approved by all authors for publication., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Conductive hydrogels have received increasing attention in the field of wearable electronics, but they also face many challenges such as temperature tolerance, biocompatibility, and stability of mechanical properties. In this paper, a double network hydrogel of MXene/TEMPO bacterial cellulose (TOBC) system is proposed. Through solvent replacement, the hydrogel exhibits wide temperature tolerance (-20-60 °C) and stable mechanical properties. A large number of hydrogen bonds, MXene/TOBC dynamic three-dimensional network system, and micellar interactions endow the hydrogel with excellent mechanical properties (elongation at break ~2800 %, strength at break ~420 kPa) and self-healing ability. The introduction of tannic acid prevents the oxidation of MXene and the loss of electrical properties of the hydrogel. In addition, the sensor can also quickly (74 ms) and sensitive (gauge factor = 15.65) wirelessly monitor human motion, and the biocompatibility can well avoid the stimulation when it comes into contact with the human body. This series of research work reveals the fabrication of MXene-like flexible wearable electronic devices based on self-healing, good cell compatibility, high sensitivity, wide temperature tolerance and durability, which can be used in smart wearable, wireless monitoring, human-machine Interaction and other aspects show great application potential., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Cellulose, an abundant and eco-friendly polymer, is a promising raw material to be used for preparing energy storage devices such as lithium-ion batteries (LIBs). Despite the significance of cellulose functional groups in LIBs components, their structure-properties-application relationship remains largely unexplored. This article thoroughly reviews the current research status on cellulose-based materials for LIBs components, with a specific focus on the impact of functional groups in cellulose-based separators. The emphasis is on how these functional groups can enhance the mechanical, thermal, and electrical properties of the separators, potentially replacing conventional non-renewal material-derived components. Through a meticulous investigation, the present review reveals that certain functional groups, such as hydroxyl groups (-OH), carboxyl groups (-COOH), carbonyl groups (-CHO), ester functions (R-COO-R'), play a crucial role in improving the mechanical strength and wetting ability of cellulose-based separators. Additionally, the inclusion of phosphoric group (-PO 3 H 2 ), sulfonic group (-SO 3 H) in separators can contribute to the enhanced thermal stability. The significance of comprehending the influence of functional groups in cellulose-based materials on LIBs performance is highlighted by these findings. Ultimately, this review explores the challenges and perspectives of cellulose-based LIBs, offering specific recommendations and prospects for future research in this area., Competing Interests: Declaration of competing interest It is the original work of the authors. All the authors mutually agree that it should be submitted to Carbohydrate Polymers. The manuscript has not been published or presented elsewhere in part or in entirety and is not under consideration by another journal. The authors declare that they have no conflict of interests. There is no research involving Human Participants and/or Animals., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Starch and modified starch, spanning various structural levels, are comprehensively reviewed, with a special emphasis on the advancement of starch and its derivative-based delivery systems for bioactive substances. The pivotal aspect highlighted is the controlled release of active ingredients by starch-based delivery systems with distinct hierarchical structures. At the molecular level, diverse categories of starch degradation products, such as dextrin and highly branched starch, serve as versatile amphiphilic carriers for encapsulating active ingredients. At the level of helical structure, the distinctive configuration of the starch-guest complex partly determines the mechanism of controlled release for diverse active components. At the crystal and particle structural level, starch assumes the role of a carrier, effectively modulating the release of active substances, and enhances the innate physiological activity of different active components. As a natural polymer molecule, starch can also generate hydrogel materials in polymer form, expanding its utility in the fields of food, materials, and even medicine., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Nanocellulose finds various applications in advanced electrical devices due to its impressive mechanical properties, thermal stability, and degradability. Cellulose nanocrystals (CNCs) with excellent dielectric properties may act as a fresh dielectric plastic. In this study, a new strategy of small molecule modification was used to improve the dielectric constant, breakdown strength, and band gap of the CNCs. The dipole moments, dipole density, and the anisotropic impact of surface groups on the dielectric constant were studied. The number of sulfates in the CNCs showed a gradient due to alkali treatment and sulfonation, which allowed for a controlled range of the dielectric constant of nanocellulose between 4.9 and 11.9. TEMPO oxidation (2,2,6,6-tetramethylpiperidine-1-oxyl) and cyanoethylation of the CNCs further increased the dielectric constant to 11.1 and 13.2, respectively, and the dielectric loss 10 -1 . By understanding and innovating organic polymer dielectrics, we can provide significant benefits to the electronics and device industries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Motivated by the quest for biocompatibility, we report on oil-in-water (O/W), high-internal-phase Pickering emulsions stabilized via complexes of mechanical cellulose nanofibrils (CNF) and food-grade cationic surfactant ethyl lauroyl arginate (LAE). The complexation of oppositely charged CNF and LAE can be held together by electrostatic interaction. Their effect on suspensions electrostatic stabilization, heteroaggregation state, and emulsifying ability was studied and related to properties of resultant interfacial tension between oil and water and 3D printing of emulsions. The Pickering system with adjustable droplet diameter and stability against creaming and oiling-off during storage was achieved resting with LAE loading. Complexes formed by LAE adjustment act as Pickering stabilizers and three-dimensional networks in emulsion system, forming a scaffold with elastoplastic rheological properties that flows above critical stress while, without any additional treatment, exhibiting the required self-standing properties for 3D printing. By understanding the properties of CNF/LAE behavior in bulk and on interfaces, printing edible functional foods of CNF/LAE-based emulgel inks has been demonstrated to enable regulation of oil release., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

In this study, hydrophobic nanochitin aerogels are synthesized via one-pot synthesis strategy and subsequent freeze-drying technique, employing nanochitin, hexanal and formaldehyde as primary components. The tert-butyl alcohol (TBA)/water binary solvents are found efficient for well mixing of hydrophilic nanochitin and hydrophobic hexanal, which is fundamental for fabricating hydrophobic aerogels with water contact angle as high as 105°. Schiff base reaction between amino groups in nanochitin and aldehyde groups in hexanal is believed to be the main reason for the successful hydrophobization of nanochitin aerogels. Additionally, formaldehyde is employed to enhance the mechanical properties of aerogels via ice templated crosslinking technique. Nanochitin aerogels prepared in this work possess surface area as high as 237 m 2 g -1 , which are believed benefiting from the TBA/water binary solvents with lower density, smaller ice crystal and convenience in freeze-drying. The ultralow density, ultrahigh porosity, and hydrophobicity nature also lead to the advanced oil adsorption (as high as 210 g g -1 ) of nanochitin aerogels. The simple preparation process, nature sustainability and excellent adsorption performance is believed rendering nanochitin aerogels as a viable alternative for the remediation of oil spills., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Phthalocyanine green is a hydrophobic pigment with excellent properties, which is usually dispersed in the organic phase. However, most organic phases are volatile and harmful to the environment and organisms. Therefore, phthalocyanine green dispersed in the aqueous phase has development potential. In this work, cellulose nanocrystals (CNCs) were used as dispersant and stabilizer to disperse phthalocyanine green in the aqueous phase. Phthalocyanine green was added to CNCs colloid to prepare phthalocyanine green suspensions with good dispersibility and stability. The particle size, zeta potential, absorbance and microstructure of the phthalocyanine green suspensions were tested and analyzed. The results showed that CNCs had good dispersibility and stability to phthalocyanine green due to charge repulsion and steric hindrance. The phthalocyanine green suspensions were nano-sized and had well compatibility with different types of coating forming substances. The coatings of the mixture had good water resistance, adhesion and mechanical properties. The suspensions had the application property and could be mixed with coating forming substances to prepare coating materials. As a renewable and easily degraded biomass resource, CNCs are expected to become a new dispersant and stabilizer for pigment., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Xylan is primarily found in the secondary cell wall of plants providing strength and integrity. To take advantage of the reinforcing effect of xylan in papermaking, it is crucial to understand its role in pulp fibers, as it undergoes substantial changes during pulping. However, the contributions of xylan that is added afterwards (extrinsic) and xylan present after pulping (intrinsic) remain largely unexplored. Here, we partially degraded xylan from refined bleached softwood kraft pulp (BSKP) and adsorbed xylan onto BSKP. Enzymatic degradation of 1 % xylan resulted in an open hand sheet structure, while adsorption of 3 % xylan created a denser fiber network. The mechanical properties improved with adsorbed xylan, but decreased more significantly after enzymatic treatment. We propose that the enhancement in mechanical properties by adsorbed extrinsic xylan is due to increased fiber-fiber bonds and sheet density, while the deterioration in mechanical properties of the enzyme treated pulp is caused by the opposite effect. These findings suggest that xylan is decisive for fiber network strength. However, intrinsic xylan is more critical, and the same properties cannot be achieved by readsorbing xylan onto the fibers. Therefore, pulping parameters should be selected to preserve intrinsic xylan within the fibers to maintain paper strength., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

An effective strategy was demonstrated to design an electromagnetic interference (EMI) shielding paper via a facile surface treatment on paper. TEMPO-oxidized cellulose nanofibers (TOCN) were first integrated with Ti 3 C 2 T x MXene, and subsequently cast onto a filter paper with cationic guar gum (CGG) in a sequential way. TOCN and CGG generated a self-assembling hydrogel and formed a MXene-containing hydrogel film on top of the filter paper. The hydrogel film enhanced the tensile strength (9.49 MPa) of composite paper, and resulted in a 17 % increase as compared to the control. The composite paper containing 80 mg MXene (namely, 2.07 mg·cm -2 ) showed a conductivity of 3843 S·m -1 and EMI shielding effectiveness (EMI SE) of 49.37 dB. Furthermore, the 2-layer assembled TC-M 80 hydrogel composite paper achieved an EMI SE of 73.99 dB. Importantly, this composite paper showed higher EMI SE and lower thickness than a lot of reported materials. The presence of TOCN and CGG also protected MXene against several solvents and the incorporation of polydimethylsiloxane (PDMS) further improved the durability of the composite paper. This work provides a novel and simple strategy to design robust, ultrathin and flexible EMI shielding materials, and it might also inspire other work in paper-based functional materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Ionically conductive hydrogels are an ideal alternative material for applications in wearable flexible sensors to monitor human health. However, producing hydrogels with both high sensitivity and excellent versatility is difficult, and their transparency and UV-blocking properties are significantly limited. Here, with mussel- and gecko-inspired biomimicry, all-biomass-based hydrogels (OGTCGs) with self-adhesive, self-healing, transparent, UV-filtering, frost-resistant, environmentally stable, antibacterial, and biocompatible properties were designed and constructed via a simple one-step approach with a water/glycerol system and borax added without any crosslinker using synergistic dynamic covalent and noncovalent chemistry. The transparency of the OGTCG hydrogel reached 81.06 %, while the added tannic acid-coated cellulose nanocrystal (TA@CNC) induced a UV-blocking effect. The OGTCG hydrogel exhibited a high toughness (218.67 kPa) and modulus (100.32 kPa) reinforced by TA@CNC. The OGTCG hydrogel showed good self-healing abilities with an efficiency of over 90 % after 6 h. In a binary solvent system, the OGTCG hydrogel had environmental stability, as illustrated by density functional theory (DFT), greatly broadening its application range. Moreover, it had an electrical conductivity of 2.3 mS cm -1 and a sensitivity of 3.97. Therefore, with its rapid response and real-time monitoring capabilities, the OGTCG hydrogel shows great potential for applications in monitoring human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

The fabrication of reusable natural polysaccharide sponges with nanoscale dispersed photocatalysts to achieve robust photocatalytic efficiency is desirable yet challenging. Herein, inspired by the nesting behavior when fishing, we designed reusable starch sponge with chemically anchored nano-ZnO into carboxylated starch matrix by thermoplastic interfacial reactions and solvent replacement for absorbing and photodegrading methylene blue (MB) in situ. The plasticization and interfacial reactions promoted a simultaneous increase in the reactivity of the starch hydroxyl/carboxyl groups and the specific surface area of ZnO. Meanwhile, the crosslinked networks of starch sponge could be adjusted by varying the ZnO and carboxylic groups contents. The results of photodegradation experiments revealed the recyclable closed-loop process of attraction-trapping-photodegradation of MB was successfully realized, achieving the effect of killing three birds with one stone. The reusable starch sponge with homogeneous dispersion of nano-ZnO by constructing three-dimensional porous channels possessed the high enrichment capacity and the remarkable photocatalysis efficiency with 150 mg/L ZnO. Under UV irradiation, the starch sponge degraded 97 % of MB with 1.67 × 10 -3  min -1 photodegradation rate constant even after five cycles, which exceeded most existing photocatalytic systems. Overall, the reusable starch sponge with adjustable structure provided new insights for multifunctional bio-based photocatalyst loading systems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

BNNS (boron nitride nanosheets)-CNF (cellulose nanofibrils) nanocomposite films have attracted increasing attention for advanced thermal management applications. However, the nanocomposite films reported so far generally suffer from unsatisfactory overall performance, especially for thermal conductivity and tensile strength. In this work, a nanocomposite film with excellent overall performance was prepared by using CCNF1.2 (carboxymethylated CNF with 1.2 mmol·g -1 carboxyl content) simultaneously as effective dispersant and reinforcement matrix for BNNS. The high aspect ratio of CCNF1.2 is primarily responsible for its excellent dispersion capability for BNNS, which provides strong steric hindrance repulsion force. Meanwhile, CCNF1.2 manifests the strongest hydrophobic-hydrophobic interactions with BNNS, and its carboxyl groups completely interact with the -OH of BNNS by hydrogen bonding. As a result, the BNNS-CCNF1.2 film (50 wt% BNNS) exhibits compacted aligned structure and superior comprehensive performance (125.0 MPa tensile strength, 17.3 W·m -1 ·K -1 in-plane thermal conductivity, and improved water resistance). This work demonstrates the effectiveness of CCNF in improving the overall performance of BNNS-CNF films and paves the way for their practical application in the advanced thermal management of next-generation electronic devices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Utilizing spent coffee grounds (SCG) to produce high value-added materials is attractive and meaningful. In this work, a multi-functional biomass film is prepared from SCG and dissolving pulp through a dissolution and regeneration process. Importantly, dissolving pulp as a reinforcing additive can significantly enhance the mechanical strength of the regenerated SCG film. The prepared composite films with SCG contents ranging from 33.33 wt% to 81.82 wt% demonstrate excellent optical and mechanical properties. The composite film with 66.67 wt% SCG exhibits outstanding UV blocking capability (99.43 % for UVB and 96.59 % for UVA) and high haze (69.22%); meanwhile, the composite film with 33.33 wt% SCG performs better mechanical strength (58.69 MPa tensile strength and 3.13 GPa Young's modulus) and superior biodegradability (fully degraded within 26 days by being buried in soil) than commercial plastic. This work generally introduces a facile and practical approach to converting waste SCG into promising materials in various fields., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Particle matter (PM) is a complex mixture of particles suspended in the air, mainly caused by fuel combustion from vehicles and industry, and has been related to pulmonary and cardiovascular diseases. The Metropolitan Area of Aburrá Valley in Colombia is the second most populous urban agglomeration in the country and the third densest in the world, composed of ten municipalities. Examining the physicochemical properties of PM is crucial in comprehending its composition and its effects on human health, as it varies based on the socioeconomic dynamics specific to each city. This study characterized the PM collected from the north, south, and central zones to evaluate its chemical composition and morphology. Different elements such as silicon, carbon, aluminum, potassium, calcium, sodium, iron, magnesium, and copper and the presence of unburned fuel, motor oil, and silicon fibers were identified. In vitro and in silico studies were conducted to evaluate the toxicity of the PM, and it was found that the PM collected from the central zone had the greatest impact on cell viability and caused DNA damage. The in silico study demonstrated that PM has concentration-dependent proarrhythmic effects, reflected in an action potential duration shortening and an increased number of reentries, which may contribute to the development of cardiac arrhythmias. Overall, the results suggest that the size and chemical composition of ambient PM can induce toxicity and play an important role in the generation of arrhythmias., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Thin films used in electronic devices are often petroleum-based, non-biodegradable, and non-renewable polymers. Herein, ultrathin ultrastrong regenerated cellulose films were made with a facile method by applying a solution of mildly carboxylated nanocellulose and various amounts of epichlorohydrin (ECH) as a crosslinker. The morphology and physiochemical properties of films were measured using FE-SEM, TEM, FTIR, NMR, UV-Vis, XRD, DLS, and TGA. Carboxylated cellulose with a charge content of 1.5 mmol/g was prepared to make alkaline dopes containing nanocrystalline cellulose (CNC). Then, ECH (0-50%) was added and the dope was blade cast, dried in an oven, regenerated in an acid bath, washed, and air dried to make uniform films approximately 1 μm thick. The tensile stress and elastic modulus of the films were measured and found to be 100-300 MPa and 5-12.7 GPa, respectively. Higher amounts of ECH led to stronger films. All films were over 96% transparent, insoluble in water, and absorbed 24-28% moisture. TGA analysis showed ultrathin films were thermally resistant up to 250 °C and were stable and unchanged over a month at 105 °C showing excellent thermal aging resistance. Overall, films with 5-10% ECH are extremely strong, which makes them promising bioresource-based candidates for flexible electronic applications., Competing Interests: Declaration of competing interest Theo G.M. van de Ven, Md. Nur Alam, Jean-philip Lumb, Md. Shahidul Islam, and Mohammadhadi Moradian have patent #WO2022221945 licensed to McGill university. The authors declare no competing financial interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The issue of mercury pollution in environmental remediation has garnered significant attention due to its severe health hazards to humans. Various strategies have been devised to mitigate the impact of toxic mercury ions, including coagulation, ion exchange, adsorption, membrane technology, and electrochemical treatment. Among these approaches, adsorption has emerged as an efficient and widely employed method for the uptake of low concentrations of mercury ions. It offers convenient operation, high removal efficiency, and facile regeneration of the adsorbent. Wood, being the most abundant renewable and sustainable bioresource, has garnered attention as a promising material for treating heavy metal wastewater. This is attributed to its unique physical and chemical characteristics, encompassing hierarchical pores, aligned channels, active functional groups, biodegradability, and cost-effectiveness. However, a comprehensive examination of the cutting-edge applications of wood and wood-derived biopolymers in the detection and removal of mercury ions from wastewater has yet to be undertaken. Consequently, this article presents a chronological overview of recent advancements in materials and structures derived from bulk wood and its constituents, including cellulose, lignin, hemicellulose, and tannin, with a specific focus on their utility in detecting and eliminating mercury from water sources. Subsequently, the most promising techniques and strategies involving wood and wood-derived biopolymers in addressing the predicament of mercury pollution are explored. Furthermore, this piece offers insights into the existing challenges and future prospects concerning environmentally friendly materials derived from wood, aiming to foster the development of cost-effective mercury adsorbents and detection devices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Morphological characterization of microfibrillated cellulose (MFC) is critically important to process control in production and product specification for trade and product development yet is extremely difficult. This study evaluated several indirect methods for relative comparison of the morphology of lignin-free and lignin-containing ((L)MFCs). The (L)MFCs studied were produced using a commercial grinder through different passes from a dry lap bleached kraft eucalyptus pulp, a virgin mixed (maple and birch) unbleached kraft hardwood pulp, and two virgin-unbleached kraft softwood (loblolly pine) pulps with one bleachable grade (low lignin content) and one liner grade (high lignin content). The (L)MFCs were indirectly characterized using techniques based on water interactions, i.e., water retention value (WRV) and fibril suspension stability, as well as fibril properties, i.e., cellulose crystallinity and fine content. Optical microscopy and scanning electron microscopy were also applied to directly visualize the (L)MFCs to provide some objective measure of the morphology of the (L)MFCs. The results indicate that most measures such as WRV, cellulose crystallinity, fine content cannot be used to compare (L)MFCs from different pulp fibers. Measures based on water interactions such as (L)MFC WRV and suspension stability appeared can provide some degree of indirect assessment. This study provided the utilities and limits of these indirect methods for relative comparison of the morphologies of (L)MFCs., Competing Interests: Declaration of competing interest The authors declare that they do not have competing interests for the work reported here., (Published by Elsevier Ltd.)

Photocurable 3D printing technology has outperformed extrusion-based 3D printing technology in material adaptability, resolution, and printing rate, yet is still limited by the insecure preparation and selection of photoinitiators and thus less reported. In this work, we developed a printable hydrogel that can effectively facilitate various solid or hollow structures and even lattice structures. The chemical and physical dual-crosslinking strategy combined with cellulose nanofibers (CNF) significantly improved the strength and toughness of photocurable 3D printed hydrogels. In this study, the tensile breaking strength, Young's modulus, and toughness of poly(acrylamide-co-acrylic acid) D /cellulose nanofiber (PAM-co-PAA) D /CNF hydrogels were 375 %, 203 % and 544 % higher than those of the traditional single chemical crosslinked (PAM-co-PAA) S hydrogels, respectively. Notably, its outstanding compressive elasticity enabled it to recover under 90 % strain compression (about 4.12 MPa). Resultantly, the proposed hydrogel can be utilized as a flexible strain sensor to monitor the motions of human movements, such as the bending of fingers, wrists, and arms, and even the vibration of a speaking throat. The output of electrical signals can still be collected through strain even under the condition of energy shortage. In addition, photocurable 3D printing technology can provide customized services for hydrogel-based e-skin, such as hydrogel-based bracelets, fingerstall, and finger joint sleeves., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

The quality of wine can be affected by excess Cu 2+ due to the occurrence of oxidation reactions or precipitation. Therefore, it is essential to use simple and effective testing methods to ensure the Cu 2+ content in wine. In this work, we designed and synthesized a rhodamine polymer fluorescent probe (PEG-R). The water solubility of PEG-R was improved by the introduction of polyethylene glycol, which improved the performance and broadened its application in the food field. The PEG-R was characterized by high sensitivity, selectivity and fast response to Cu 2+ and was able to complete the response process within 30 s, with approximately 29-fold fluorescence enhancement of the probe after exposure to Cu 2+ , the limit of detection (LOD) was 1.295 × 10 -6 M. The probe can be used for the determination of Cu 2+ in living cells, zebrafish, white wine and food products, and it was made into practical gels and test strips., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

High conductive and transparent hydrogels with adhesion function are ideal candidates for soft electronic devices. However, it remains a challenge to design appropriate conductive nanofillers to endow hydrogels with all these characteristics. The 2D MXene sheets are promising conductive nanofillers for hydrogels due to excellent electricity and water-dispersibility. However, MXene is quite susceptible to oxidation. In this study, polydopamine (PDA) was employed to protect the MXene from oxidation and meanwhile endow hydrogels with adhesion. However, PDA coated MXene (PDA@MXene) were easily flocculated from dispersion. 1D cellulose nanocrystals (CNCs) were employed as steric stabilizers to prevent the agglomeration of MXene during the self-polymerization of dopamine. The obtained PDA coated CNC-MXene (PCM) sheets display outstanding water-dispersible and anti-oxidation stability and are promising conductive nanofillers for hydrogels. During the fabrication of polyacrylamide hydrogels, the PCM sheets were partially degraded into PCM nanoflakes with smaller size, leading to transparent PCM-PAM hydrogels. The PCM-PAM hydrogels can self-adhere to skin, and possess high transmittance of 75 % at 660 nm, superior electric conductivity of 4.7 S/m with MXene content as low as 0.1 % and excellent sensitivity. This study will facilitate the development of MXene based stable, water-dispersible conductive nanofillers and multi-functional hydrogels., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Tobacco based cellulose nanofiber (TCNF) is a novel nanocellulose that has recently been used to replace undesirable wood pulp fibers in the preparation of reconstructed tobacco sheets (RTS). However, given the strict requirements for controlling toxic chemical content in tobacco products, there is a global interest in developing a green, efficient, and toxic-chemical free approach to isolate TCNF from tobacco stem as a bioresource. In this study, we propose a creative and environmentally friendly method to efficiently and safely isolate TCNF from tobacco stem pulp, which involves integrated biological pretreatment followed by a facile mechanical defibrillation process. Feruloyl esterase is used to pretreat the stem pulp by disrupting the ether and ester bonds between lignin and polysaccharide carbohydrates within the fiber wall, which effectively facilitates cellulase hydrolysis and swelling of the stem pulp fiber, as well as the following mechanical shearing treatment for TCNF isolation. The results demonstrate that TCNF obtained by the comprehensive feruloyl esterase/cellulase/mechanical process exhibit uniform and well-dispersed nanofiber morphology, higher crystallinity, and stronger mechanical properties than those of the control. The addition of 0.5 % TCNF can replace wood pulp by 18 wt% ~ 25 wt% in the production of RTS samples while maintaining their reasonable strength properties., Competing Interests: Declaration of competing interest The authors declare that they have no know competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Polysaccharides are excellent network formers and are often processed into films from water solutions. Despite being hydrophilic polysaccharides, the typical xylans liberated from wood are sparsely soluble in water. We have previously suggested that an additional piece to the solubilization puzzle is modification of the xylan backbone via oxidative cleavage of the saccharide ring. Here, we demonstrate the influence of the degree of modification, i.e., degree of oxidation (DO) on xylan solubilization and consequent film formation and stability. Oxidized and reduced wood xylans (i.e., dialcohol xylans) with the highest DO (77 %) within the series exhibited the smallest hydrodynamic diameter (d h ) of 60 nm in dimethylsulfoxide (DMSO). We transferred the modified xylans into films credit to their established solubility and then quantified the film water interactions. Dialcohol xylans with intermediate DOs (42 and 63 %) did not form continuous films. The films swelled slightly when subjected to humidity. However, the film with the highest DO demonstrated a significant moisture uptake that depended on the film mass and was not observed with the other modified grades or with unmodified xylan., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Huge electronic wastes motivated the flourishing of biodegradable electrically conductive cellulosic paper-based functional materials as flexible wearable devices. However, the relatively low sensitivity and unstable output in combination with poor wet strength under high moisture circumstances impeded the practical application. Herein, a superhydrophobic cellulosic paper with ultrahigh sensitivity was proposed by innovatively employing ionic sodium carboxymethyl cellulose (CMC) as bridge to reinforce the interfacial interaction between carbon black (CB) and multilayer graphene (MG) and SiO 2 nanoparticles as superhydrophobic layer. The resultant paper-based (PB) sensor displayed excellent strain sensing behaviors, wide working range (-1.0 %-1.0 %), ultrahigh sensitivity (gauge factor, GF = 70.2), and satisfied durability (>10,000 cycles). Moreover, the superhydrophobic surface offered well waterproof and self-cleaning properties, even stable running data without encapsulation under extremely high moisture conditions. Impressively, when the fabricated PB sensor was applied for electronic-skin (E-skin), the signal capture of spatial strain of E-skin upon bodily motion was breezily achieved. Thus, our work not only provides a new pathway for reinforcing the interfacial interaction of electrically conductive carbonaceous materials, but also promises a category of unprecedentedly superhydrophobic cellulosic paper-based strain sensors with ultra-sensitivity in human-machine interfaces field., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Two kinds of nanocellulose (cellulose nanofibrils (CNFs) and cellulose nanocrystals (CNCs) were synthesized from pomelo peels via a facile approach of TEMPO oxidation and sulfuric acid treatment respectively. The FTIR results illustrated that hemicelluloses and lignin were completely removed from the pomelo peel cellulose substrate. The obtained CNFs and CNCs possessed a uniform morphology and nanoscale particle size. The stability of CNF-based Pickering emulsions was higher than that of emulsions stabilized with CNCs, due to the formation of gel structure induced by the CNFs' longer fibrils. Increased oil fractions enhanced the viscoelasticity of CNF-based Pickering emulsions. The in vitro digestion results suggested that increased oil fractions decreased the lipolysis degree, as a result of the larger droplet size and higher viscoelasticity of emulsion. The release of lycopene showed a trend similar to that of FFA release, suggesting that higher oil fractions were beneficial for controlling lycopene release during gastrointestinal digestion., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Separating films with both high efficiency and large flux are desperately needed to meet the rising demand for the treatment of oily wastewater, while traditional oil/water separation papers with high separation efficiency usually suffered from low flux due to the unsuitable size of filtration pores. Herein, we report a bio-based porous, superhydrophobic, and antimicrobial hybrid cellulose paper with tunable porous structures for high flux oil/water separation. The size of pores in the hybrid paper can be tuned by both physical supports provided by the chitosan fibers and the chemical shielding supplied by the hydrophobic modification. The hybrid paper with increased porosity (20.73 μm; 35.15 %) and excellent antibacterial properties can efficiently separate a wide range of oil/water mixtures, solely by gravity, with outstanding flux (maximum of 23,692.69 L m -2  h -1 ), tiny oil interception, and high efficiency of over 99 %. This work provides new sights in the development of durable and low-cost functional papers for rapid and efficient oil/water separation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The addition of urea in pre-cooled alkali aqueous solution is known to improve the dope stability of cellulose solution. However, its thermodynamic mechanism at a molecular level is not fully understood yet. By using molecular dynamics simulation of an aqueous NaOH/urea/cellulose system using an empirical force field, we found that urea was concentrated in the first solvation shell of the cellulose chain stabilized mainly by dispersion interaction. When adding a glucan chain into the solution, the total solvent entropy reduction is smaller if urea is present. Each urea molecule expelled an average of 2.3 water molecules away from the cellulose surface, releasing water entropy that over-compensates the entropy loss of urea and thus maximizing the total entropy. Scaling the Lennard-Jones parameter and atomistic partial charge of urea revealed that direct urea/cellulose interaction was also driven by dispersion energy. The mixing of urea solution and cellulose solution in the presence or absence of NaOH are both exothermic even after correcting for the contribution from dilution., Competing Interests: Declaration of competing interest There are no conflicts of interest to declare., (Copyright © 2023. Published by Elsevier Ltd.)