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Woody biomass is an abundant renewable resource. In this study, aerogels for versatile triboelectric devices are fabricated from poplar biomass via a dissolution‐and‐regeneration method with concentrated lithium bromide solution as the solvent. To improve the aerogels' structural homogeneity, two treatments—ball‐milling the raw poplar woody biomass before its dissolution, and, separately, ultrasonication following its dissolution—were applied. These treatments altered the porous structures and mechanical properties of the resulting aerogels, leading to a marked increase in their triboelectric performance. Removing the majority of the lignin from the aerogels was also explored, and resulted in triboelectric output ≈5 times greater than that of pristine woody biomass aerogel (i.e., without ball milling, ultrasonication, or lignin reduction). The underlying mechanisms of such increases were found to be both chemical and physical. Next, triboelectric devices were fabricated using the optimal (i.e., low‐lignin) aerogel for energy harvesting and biomechanical monitoring. These devices were able to: 1) respond sensitively to force, likely due to the aerogel's porous structures; 2) capture mechanical energy, charge capacitors, and power small portable electronics; and 3) monitor biomechanical movements including respiration, joint motions, and gait‐pattern changes. [ABSTRACT FROM AUTHOR]

With natural biodegradability and bio-renewability, lignocellulose has attracted great interest in the field of energy storage. Due to the porous structure, good thermal and chemical stability, and tunable surface chemistry, lignocellulose has been widely used in supercapacitors and batteries, functionalizing as electrolytes, electrodes, separators, and binders. More specifically, lignocellulose is flexible and can be combined with various polymers to produce solid-state electrolytes. On the other hand, lignocellulose can be carbonized or compounded with conductive materials to make flexible electrodes. In addition, lignocellulose can also be used to prepare sustainable binders and separators in energy storage devices to improve the stability and electrochemical properties. This review discusses the latest research on the fabrication of lignocellulose-based materials for energy storage applications. Lignocellulose-based materials as electrolytes, electrodes, separators and binders in supercapacitors and batteries are elaborated, respectively. Finally, a vision of the future regarding the challenges and their possible solutions are presented. [Display omitted] ● The main components of lignocellulose are briefly introduced. ● The preparation of lignocellulosic materials for supercapacitors and batteries are elaborated. ● The prospects and challenges of lignocellulosic materials for use in energy storage devices are presented. [ABSTRACT FROM AUTHOR]

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Hydrogels with prominent flexibility, versatility, and high sensitivity play an important role in the design and fabrication of wearable sensors. In particular, these flexible conductive hydrogels exhibit elastic modulus that is highly compatible with human skin, demonstrating the great potential for flexible sensing. However, the preparation of high-performance hydrogel-based sensors that can restrain extreme cold conditions is still challenging. Herein, a novel anti-freezing composite hydrogel with superior conductivity based on polyacrylamide (PAM), LiCl, and PEDOT:PSS coated cellulose nanofibrils (PAM/PEDOT:PSS/CNF) is constructed. The addition of CNF increased the hydrogen bonding sites of the molecular chains in the micro, thus improving the mechanical strength and the conductivity of the hydrogel in the macro. The hydrogels achieve a high tensile strength of 0.19 MPa, compressive strength of 0.92 MPa, and dissipation energy of 41.9 kJ/m3. Otherwise, LiCl increases the interactions between the colloidal phase and water molecules, endowing the hydrogels with excellent freezing tolerance. Specifically, the optimized hydrogel of 45 % LiCl exhibited stable mechanical properties at −40 °C. Finally, the composite hydrogel was used to assemble flexible sensors with high sensitivity of 10.3 MPa−1, which can detect a wide range of human movements and physiological activities. [Display omitted] [ABSTRACT FROM AUTHOR]

Construction of composite Zn anode with highly conductive frame can effectively homogenize the interfacial electric field and charge distribution, thereby effectively inhibiting the formation of dendrites of aqueous Zn-ion batteries. Herein, highly conductive nanocellulose-based carbon aerogels with honeycomb porous structure and high specific surface area were synthesized by bidirectional freezing and carbonization. Dendrite-free Zn@Carbon Aerogel (Zn@CA) composites were prepared by facile electrodeposition. Benefiting from the ordered porous structure of nanocellulose-based carbon aerogels, Zn was uniformly dispersed on carbon aerogels. The carbon aerogels with connected conductive network can adjust the nucleation sites of Zn, thus inhibiting the formation of dendrites. Zn@CA composite electrode material exhibits high specific surface area and hydrophilicity (water contact angle of 37.8°), and owns rapid electron transfer channels. The assembled symmetrical cells with Zn@CA electrodes exhibit lower polarization voltage, excellent cycling performance, and almost 100% Coulombic efficiency as well as fast electrochemical kinetics during repeated Zn plating/stripping processes for 13,000 cycles. [Display omitted] • Zn@Nanocellulose-based carbon aerogels were prepared for inhibiting zinc dendrites. • The ordered conductive network offers homogenize interfacial electric field. • The composite electrode exhibits high specific surface area and hydrophilicity. • The symmetrical cell shows lower polarization and stable cycling performance. [ABSTRACT FROM AUTHOR]

Lignocellulosic nanofibrils (LCNFs) are isolated from poplar sawdust via a sustainable preparation approach based on recyclable p-toluenesulfonic acid (p-TsOH) treatment and high-pressure homogenization. The obtained LCNFs show a network structure with a width of 15–30 nm and a length up to several micrometers. When hydrolysis duration is less than 60 min, the LCNFs exhibit high crystallinity (62.32%), good thermal stability (T max = 367 °C), and fine dispersibility in water. Lignocellulose nanopapers (LCNP) are prepared using the LCNFs via simple vacuum filtration, which show superior mechanical performance and excellent UV-blocking function. The optimized LCNP presents high mechanical strength (up to 164.0 MPa) and toughness (up to 12.3 MJ/m3), as well as good flexibility. We conclude that LCNF-derived LCNP can be finely adjusted by varying the residual lignin content, providing a rationale for LCNFs selection. This work offers a sustainable, optimized strategy for valorization and full utilization of low-value poplar sawdust into value-added LCNFs and LCNP. [Display omitted] • Lignocellulosic nanofibrils (LCNFs) were prepared using recyclable p-TsOH. • The optimal LCNFs exhibited uniform width distribution and fine dispersibility. • A series of lignocellulose nanopapers was prepared from LCNFs by vacuum filtration. • The LCNPs showed excellent mechanical properties and superior UV-blocking capability. [ABSTRACT FROM AUTHOR]

Herein, a highly efficient and sustainable approach, namely HCl-catalyzed para-toluene sulfonic acid/Formic acid (p-TsOH/FA) hydrolysis was reported to produce surface functionalized cellulose nanocrystals (CNCs). The optimized CNCs showed a high yield (79.6 %), high crystallinity (70.6 %) and high thermal stability (maximal weight loss temperature around 350 °C). In addition, the as-prepared CNCs possess excellent ability to stabilize oil-water due to the introduction of functional formyl groups, which could be promising stabilizers for Pickering emulsions (PEs). At a fixed oil-water ratio (2:8, v:v), the CNCs with the concentration of 0.5 wt% to 2.0 wt% could stabilize peanut oil to make PEs, and the emulsion droplets were <5 μm in diameter. In addition, the stability of the PEs at different temperature, pH, ionic strength, and long storage time were studied. The results indicated that the obtained CNCs could be sustainable and superior stabilizers for PEs. [Display omitted] • Amphiphilic CNCs were prepared from bleached pulp by HCl-catalyzed organic acid hydrolysis. • Both sulfonyl and formyl groups were introduced on the surface of CNCs. • The maximum yield of CNCs was 79.6 % based on the bleached pulp. • The obtained CNCs could stabilize peanut oil to make Pickering emulsions. • The Pickering emulsions exhibited good pH and temperature stability. [ABSTRACT FROM AUTHOR]

• Developing the capability of GAN for the prognosis prediction. • Adding the clinical data as conditions to the training process. • Using Wasserstein distance and gradient penalty to make the training process more stable. Background and Objective: Generative adversarial network (GAN) is able to learn from a set of training data and generate new data with the same characteristics as the training data. Based on the characteristics of GAN, this paper developed its capability as a tool of disease prognosis prediction, and proposed a prognostic model PregGAN based on conditional generative adversarial network (CGAN). Methods: The idea of PregGAN is to generate the prognosis prediction results based on the clinical data of patients. PregGAN added the clinical data as conditions to the training process. Conditions were used as the input to the generator along with noises. The generator synthesized new samples using the noises vectors and the conditions. In order to solve the mode collapse problem during PregGAN training, Wasserstein distance and gradient penalty strategy were used to make the training process more stable. Results: In the prognosis prediction experiments using the METABRIC breast cancer dataset, PregGAN achieved good results, with the average accurate (ACC) of 90.6% and the average AUC (area under curve) of 0.946. Conclusions: Experimental results show that PregGAN is a reliable prognosis predictive model for breast cancer. Due to the strong ability of probability distribution learning, PregGAN can also be used for the prognosis prediction of other diseases. [ABSTRACT FROM AUTHOR]

An important phenomenon of Kirkendall effect is the presence of voids that formed during diffusion, which may crack the mechanical properties. In this paper, a cellular automaton (CA) based model is developed to simulate the voids formation and evolution process of Kirkendall effect. Firstly, this paper derives the critical radius of voids nucleation and the nucleation rate. Secondly, this paper derives the growth rate of Kirkendall voids, and the relationship between the movement of interface plane and the growth rate of voids. According to the formulas derived from this paper, the number of voids and the average radius of voids can be inferred by observing the shift velocity of interface plane between the different metals. Theoretical analysis is helpful for the fundamental understanding of the underlying mechanisms of Kirkendall voids, and is helpful for the study on suppressing the formation of Kirkendall voids. Thirdly, this paper presents a numerical simulation on Kirkendall voids formation and evolution process based on cellular automaton, which provides an intuitive visual process of Kirkendall voids growth and the movement of interface plane. • This paper derives the critical radius of voids nucleation and the nucleation rate. • This paper derives the growth rate of Kirkendall voids, and the relationship between the movement of interface plane and the growth rate of voids. [ABSTRACT FROM AUTHOR]

The growing demand for electronic devices has led to excessive stress on Earth's resources, necessitating effective waste management and the search for renewable materials with minimal environmental impact. Bioelectronics, designed to interface with the human body, have traditionally been made from inorganic materials, such as metals, which, while having suitable electrical conductivity, differ significantly in chemical and mechanical properties from biological tissues. This can cause issues such as unreliable signal collection and inflammatory responses. Recently, natural biopolymers such as cellulose, chitosan, and silk have been explored for flexible devices, given their chemical uniqueness, shape flexibility, ease of processing, mechanical strength, and biodegradability. Cellulose is the most abundant natural biopolymer, has been widely used across industries, and can be transformed into electronically conductive carbon materials. This review focuses on the advancements in cellulose-based conductive materials for bioelectronics, detailing their chemical properties, methods to enhance conductivity, and forms used in bioelectronic applications. It highlights the compatibility of cellulose with biological tissues, emphasizing its potential in developing wearable sensors, supercapacitors, and other healthcare-related devices. The review also addresses current challenges in this field and suggests future research directions to overcome these obstacles and fully realize the potential of cellulose-based bioelectronics., (© 2024 Wiley‐VCH GmbH.)

2,5-Furandicarboxylic acid (FDCA) is a class of valuable biomass-based platform compounds. The creation of FDCA involves the catalytic oxidation of 5-hydroxymethylfurfural (HMF). As a novel catalytic method, electrocatalysis has been utilized in the 5-hydroxymethylfurfural oxidation reaction (HMFOR). Common noble metal catalysts show catalytic activity, which is limited by price and reaction conditions. Non-noble metal catalyst is known for its environmental friendliness, affordability and high efficiency. The development of energy efficient non-noble metal catalysts plays a crucial role in enhancing the HMFOR process. It can greatly upgrade the demand of industrial production, and has important research significance for electrocatalytic oxidation of HMF. In this paper, the reaction mechanism of HMF undergoes electrocatalytic oxidation to produce FDCA are elaborately summarized. There are two reaction pathways and two oxidation mechanisms of HMFOR discussed deeply. In addition, the speculation on the response of the electrode potential to HMFOR is presented in this paper. The main non-noble metal electrocatalysts currently used are classified and summarized by targeting metal element species. Finally, the paper focus on the mechanistic effects of non-noble metal catalysts in the reaction, and provide the present prospects and challenges in the electrocatalytic oxidation reaction of HMF., (© 2024 Wiley‐VCH GmbH.)

Strong interfacial adhesion between cellulose and other polymers is critical to achieve the properties required for specific applications in composite materials. Here, we developed a method for the simultaneous homogeneous dissolution of cellulose and thermoplastic polyurethane (TPU) in 1,8-diazabicyclo (5.4.0) undec-7-ene levulinate/dimethyl sulfoxide ([DBUH]Lev/DMSO) solvent. This process is essential for preparing cellulose/TPU composite films and fibers through interaction-modulated cellulose regeneration. Both cellulose and TPU can be easily dissolved together in [DBUH]Lev/DMSO solvent under mild conditions. The resulting cellulose/TPU solutions exhibited strong temperature sensitivity, shear-thinning behavior and viscoelasticity, making them suitable for cast films and continuous spinning. More importantly, research findings, including density functional theory calculations and experimental characterization, confirmed the high compatibility and interaction modulability of cellulose and TPU in the composite films. The representative C90T10 sample (cellulose/TPU, 90/10) showed high transparency (90 % at 800 nm) and excellent mechanical properties (tensile strength: 176 MPa; elongation at break: 8.1 %). Additionally, the maximum tensile strength and elongation at the break of the composite fiber from C90T10 were 214 MPa and 48.1 %, respectively. This method may provide a feasible approach to design and produce homogeneous environmentally friendly composites of cellulose and other polymers at the molecular level., 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 recent years, the pursuit of high-performance nano-flexible electronic composites has led researchers to focus on nanocellulose-graphene composites. Nanocellulose has garnered widespread interest due to its exceptional properties and unique structure, such as renewability, biodegradability, and biocompatibility. However, nanocellulose materials are deficient in electrical conductivity, which limits their applications in flexible electronics. On the other hand, graphene boasts remarkable properties, including a high specific surface area, robust mechanical strength, and high electrical conductivity, making it a promising carbon-based nanomaterial. Consequently, research efforts have intensified in exploring the preparation of graphene-nanocellulose flexible electronic composites. Although there have been studies on the application of nanocellulose and graphene, there is still a lack of comprehensive information on the application of nanocellulose/graphene in flexible electronic composites. This review examines the recent developments in nanocellulose/graphene flexible electronic composites and their applications. In this review, the preparation of nanocellulose/graphene flexible electronic composites from three aspects: composite films, aerogels, and hydrogels are first introduced. Next, the recent applications of nanocellulose/graphene flexible electronic composites were summarized including sensors, supercapacitors, and electromagnetic shielding. Finally, the challenges and future directions in this emerging field was discussed., 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 B.V. All rights reserved.)

Multifunctional architecture with intriguing structural design is highly desired for realizing the promising performances in wearable sensors and flexible energy storage devices. Cellulose nanofiber (CNF) is employed for assisting in building conductive, hyperelastic, and ultralight Ti 3 C 2 T x MXene hybrid aerogels with oriented tracheid-like texture. The biomimetic hybrid aerogels are constructed by a facile bidirectional freezing strategy with CNF, carbon nanotube (CNT), and MXene based on synergistic electrostatic interaction and hydrogen bonding. Entangled CNF and CNT "mortars" bonded with MXene "bricks" of the tracheid structure produce good interfacial binding, and superior mechanical strength (up to 80% compressibility and extraordinary fatigue resistance of 1000 cycles at 50% strain). Benefiting from the biomimetic texture, CNF/CNT/MXene aerogel shows ultralow density of 7.48 mg cm -3 and excellent electrical conductivity (~ 2400 S m -1 ). Used as pressure sensors, such aerogels exhibit appealing sensitivity performance with the linear sensitivity up to 817.3 kPa -1 , which affords their application in monitoring body surface information and detecting human motion. Furthermore, the aerogels can also act as electrode materials of compressive solid-state supercapacitors that reveal satisfactory electrochemical performance (849.2 mF cm -2 at 0.8 mA cm -2 ) and superior long cycle compression performance (88% after 10,000 cycles at a compressive strain of 30%)., (© 2023. The Author(s).)

Cellulose nanopaper has shown great potential in diverse fields including optoelectronic devices, food packaging, biomedical application, and so forth, owing to their various advantages such as good flexibility, tunable light transmittance, high thermal stability, low thermal expansion coefficient, and superior mechanical properties. Herein, recent progress on the fabrication and applications of cellulose nanopaper is summarized and discussed based on the analyses of the latest studies. We begin with a brief introduction of the three types of nanocellulose: cellulose nanocrystals, cellulose nanofibrils and bacterial cellulose, recapitulating their differences in preparation and properties. Then, the main preparation methods of cellulose nanopaper including filtration method and casting method as well as the newly developed technology are systematically elaborated and compared. Furthermore, the advanced applications of cellulose nanopaper including energy storage, electronic devices, water treatment, and high-performance packaging materials were highlighted. Finally, the prospects and ongoing challenges of cellulose nanopaper were summarized., (© 2022. The Author(s).)

This work demonstrated a facile and sustainable approach to functionalize cellulose nanopaper (CNP) by impregnation of chitosan (CS) and the followed halogenation. It was found that the tensile strength of the functionalized CNP (CNP/CS-Cl) was enhanced by 38.3% and 512.6% at dry and wet conditions, respectively. Meanwhile, the total transmittance (at 550 nm) of CNP/CS-Cl was increased from 75% of pure CNP to 85%, with 35% decrease in optical haze. Moreover, the CNP/CS-Cl exhibited significant enhancement in barrier properties. Importantly, part of the amino groups on CS were transformed into N-halamines during the halogenation process, which endowed the CNP/CS-Cl with excellent antibacterial performance against both S. aureus and E. coli with 100% bacterial reduction after 10 min of contact. Thus, this work provides a simple and efficient approach to functionalize CNP with water resistance, high transparency, excellent antibacterial and barrier properties, which will expand the potential applications of CNP., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Developing green and simple methods for the preparation of cellulose nanofibrils (CNFs) is of great significance. Herein, a green deep eutectic solvent (DES) system based on choline chloride (ChCl) and citric acid (CA) is employed to pretreat cellulose fibers for the preparation of CNFs. The effect of the pretreatment temperature on the chemo-physical properties of the CNFs is comprehensively investigated. A high CNFs yield of up to 84.19% can be achieved under optimized conditions. The optimal CNFs show a narrow diameter distribution and length up to several microns, high crystallinity and thermal stability, as well as excellent dispersibility in water. Furthermore, semi-transparent and flexible cellulose nanopaper (CNP) was fabricated through a facile vacuum filtration process. The optimal CNP shows high tensile strength (175.15 MPa) and toughness (7.51 MJ/m 3 ). Therefore, this work provides a sustainable and facile approach to fabricate CNFs and CNP, which can be potentially used for various high-tech applications., (Copyright © 2021. Published by Elsevier Ltd.)

In this work, a sustainable and highly efficient approach for preparing bifunctional cellulose nanocrystals (CNCs) was proposed through a mixed acid system of sulfuric acid and formic acid (FA). It was found that low-concentration (5-10 wt%) sulfuric acid can significantly improve the hydrolysis efficiency of FA (65-80 wt%), which enabled the highly efficient preparation of CNCs, i.e., the maximum yield of CNCs reached up to 70.65%. The obtained CNCs exhibited a rod-like shape with high crystallinity, and good dispersibility in both water and some organic phases. Moreover, the as-prepared CNCs exhibited high thermal stability, which is much higher than that of the traditionally sulfuric acid hydrolyzed ones. In addition, it was demonstrated that the bifunctional CNCs were able to stabilize various oils to form stable Pickering emulsion gels. Thus, this work provides a promising approach for sustainable preparation of bifunctional CNCs, which may find high-end applications in diverse fields., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The purpose of this review is to summarize and discuss the recent developments in exploring cellulose and its derivatives in the applications of oilfield chemicals for petroleum drilling and exploiting. We begin with a brief introduction of cellulose and its common water-soluble derivatives, such as the carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose, and amphoteric cellulose. Afterwards, the applications of cellulose derivatives in different petroleum exploitation processes, such as drilling, cementing, and fracturing, are set out in detail. Finally, the application perspectives and challenges of cellulose derivatives for oilfield applications are presented. This work demonstrates that cellulose derivatives have wide application prospects in oilfield industry in the future., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

As a kind of agro-industrial wastes, paper mill sludge (PMS) has posed serious environmental and economic challenges for disposal due to the more stringent regulations and diminishing land availability in recent years. The present study is aimed at providing a sustainable approach to efficiently convert PMS to cellulose nanofibrils (CNFs) and cellulose nanopaper (CNP) by formic acid (FA) hydrolysis pretreatment and the followed microfluidization. It is found that FA hydrolysis (4-6 h) could swell and shorten PMS fibers, and only two-pass microfluidization is sufficient to get uniform CNFs from the collected cellulose residual. Results indicate that the obtained CNFs show high thermal stability and crystallinity index, surface functionality (ester groups), as well as a high yield of over 75 wt.%. Notably, more than 90 % FA can be recovered and the hydrolyzed sugars could be potentially used to produce platform chemicals (e.g. lactic acid, furfural). Finally, transparent CNP is prepared from the CNFs suspension via a simple vacuum filtration technique. The resultant CNP shows good mechanical properties with the maximum tensile strength and toughness of 106.4 MPa and 6.62 MJ/m 3 , respectively. Therefore, the current work provides a green and sustainable method to valorize PMS for the production of valuable CNFs and CNP., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Over the past few years, wearable electronics and smart textiles have seen tremendous growth in both academia and industries. However, it is still a challenge to prepare robust, flexible, wearable, and multiresponsive textile electronics. A newly blooming two-dimensional (2D) transition-metal carbide/nitride (MXene) is regarded as an ideal active material to build multifunctional electronics due to its intriguing properties. Herein, a hydrophobic and multifunctional textile composite (Si-MAP) was prepared by decoration of conductive MXene nanosheets onto air-laid paper, followed by wrapping with poly(dimethylsiloxane) (PDMS). These obtained smart textiles exhibited excellent electronic/photonic/mechanical triresponsive properties: Si-MAPs could reach high equilibrium temperatures (104.9 and 118.7 °C) under quite low power illumination (1.25 W cm -2 ) and working voltage (4 V). The Si-MAP pressure sensor exhibited high sensitivity and rapid response time (30-40 ms), which can capture a wide range of human movements. Moreover, the thin PDMS layer not only rendered the textile composites hydrophobic but also improved the stability and adaptation for daily use. Remarkably, the hydrophobic Si-MAPs have maintained the advantages of breathability and washability, which make them suitable for wearing. Thus, this smart Si-MAP textile provides a reference for the study of the next generation of light, portable, and wearable textile-based electronic devices.