The effects of the composition, morphology, particle size and pore size distribution on the electrochemical properties of bagasse and corn straw derived hard carbon materials prepared by one-step carbonization were investigated. The results show that the hard carbon material derived from corn stalk has larger layer spacing, smaller pore diameter and smaller particle size, which shows better sodium storage performance. The corn straw hard carbon material showed excellent electrochemical properties at the current density of 50 mA/g, and its reversible capacity reached 274 mAh/g and a high ICE of 89%. A good capacity retention of 97% after 100 cycles. It is worth pointing out that the material also exhibits a reversible capacity of 217 mAh/g at 1 000 mA/g.

The separator is a crucial component in lithium batteries. Commercially available polyolefin separators often suffer from poor electrolyte wettability and high-temperature shrinkage, which limits their suitability for the development of high-performance lithium batteries. In this study, a cellulose/polyacrylamide (d-CA/PAM) composite separator was prepared by in situ polymerization of acrylamide in a cellulose acetate (CA) solution, followed by synchronous phase separation and deacetylation. The d-CA/PAM separator exhibits high porosity (77.9%), excellent electrolyte uptake (273.0%), outstanding thermal stability (no shrinkage at 200 ℃), and a high ionic conductivity (1.51 mS/cm). The lithium metal batteries assembled with the d-CA/PAM separator demonstrate superior performance compared to polyolefin separators, showing a higher initial capacity (150.1 mAh/g vs. 143.0 mAh/g) and better cycling stability (capacity retention after 100 cycles 94.3% vs. 92.0%).

Ti₃C₂T_x MXene flexible film is composed of metallic carbon/nitride stacked with two-dimensional layered structure, exhibiting excellent photothermal conversion performance. However, due to the intermolecular interaction between the MXene layers, the presence of water molecules is easy to reduce the binding force, thus affecting the stability of the flexible film. To solve the stability problem of MXene flexible film, the Ti₃C₂T_x MXene nanosheets with a certain thickness and surface rich in hydroxyl and other functional groups were obtained by using lithium fluoride and concentrated hydrochloric acid etching, combined with ultrasonic peeling, and a certain concentration of nanocellulose (CNC). Subsequently, the surface of the film was chemically modified with perfluorodecyl trimethoxysilane modifier, and the hydrophobic flexible film material with cellulose as the skeleton was obtained. The microstructure and surface functional groups of the composite film were systematically characterized, and then the mechanical properties were tested to determine the optimization of infiltration, photothermal and mechanical properties of the film by adding cellulose and hydrophobic modification. The results show that the maximum heating rate of the prepared composite film is 115 ℃/min, the contact Angle with water is 129.8°, the maximum tensile lifting rate can reach 157.95%, showing good photothermal, hydrophobic and mechanical properties.

P(AM-co-AMPSLi) composite conductive hydrogels were prepared by copolymerization of 2-acrylamido-2-methyl propane sulfonic acid lithium (AMPSLi) and AM. Cellulose nanocrystals (CNC) were selected as the reinforcement phase to improve the mechanical properties of the hydrogels. The structure, mechanical properties, electrical conductivity and microstructure of the composite hydrogels were measured and studied. The results showed that the hydrogen bond between CNC and P(AM-co-AMPSLi) hydrogels could significantly improve the comprehensive mechanical properties of hydrogels. The electrical conductivity of 3%CNC/P(AM-co-5%AMPSLi) composite hydrogel (0.65 S/m) and the comprehensive mechanical properties were the best (the maximum load and tensile strength of 0.473 N and 30.37 kPa, respectively). The tensile strength was 420% higher than that of the copolymer hydrogel without CNC.

Bacterial cellulose has a unique three-dimensional network structure with high porosity, mechanical strength and good biocompatibility, which is beneficial for cell growth. It can be an ideal candidate for artificial blood vessels, tissue engineering, and wound excipients, and as well as one of the hotspots in biomedical material research. However, due to the fact that BC itself does not possess functional characteristics such as antibacterial, myogenic, and hemostatic properties, its further application in the medical field is limited. Therefore, by introducing functional polymers, carbon based nanomaterials, and metal nanoparticles into BC through ex-situ and in-situ modification methods, composite materials with enhanced functional properties are obtained. The modified BC materials have shown great potential for application in this field. This review provides a detailed introduction to the preparation and functionalization modification of BC, and summarizes its main achievements in the medical field in recent years, providing reference for the development of low-cost, green, safe, and multifunctional medical materials.

Cellulose ether (hydroxyethyl cellulose ether, hydroxypropyl methyl cellulose ether) was used to modify the bonding properties of fly ash-based thin spray materials, and the effects of viscosity and substituent of cellulose ether on the bonding strength, consistency, and its tensile strength and compressive strength of the fly ash-based thin spray materials were studied, and the microstructure of the fly ash-based thin spray materials before and after the incorporation of cellulose ether into the 28 d specimens was studied by scanning electron microscopy. The results showed that the bond strength of the thin-sprayed materials was significantly improved af ter the addition of cellulose ether, with a maximum increase of 294.23% compared with that of the unadulterated cellulose ether group. Under the same substituent, the bonding performance of the cellulose ether samples with low viscosity was higher. Under different substituents, the bond strength of hydroxyethyl cellulose ether specimens was higher, and the adverse effect on mechanical properties was smaller. The 28 d bond strength of fly ash-based thin spray material incorporated with 0.05% (mass percentage of cementitious material) hydroxyethyl cellulose ether (HEC) reached 1.67 MPa, and the compressive strength was 11.4 MPa.

To broaden the high-value utilization of distiller's grain, the application potential of cellulose nanocrystals (CNCs) prepared from distiller's grain in the field of wastewater treatment was explored. Firstly, cellulose from the distiller's grain was extracted by washing, bleaching, and alkali treatment, and then the extracted cellulose was hydrolyzed by 50%(v/v) sulfuric acid at 1∶20 solid-liquid ratio to prepare the distiller's grain CNCs. Their chemical composition was determined and their chemical structure was characterized. Finally, the adsorption capacity of distiller's grain CNCs to methylene blue and congo red solution was studied. Results found that the purity of cellulose in the prepared CNCs from the distiller's grain was more than 90%, and the particle size distribution was concentrated in 180-300 nm. The zeta-potential value of the prepared CNCs was measured as -30.1 mV. Furthermore, the equilibrium adsorption rates of the distiller's grain CNCs on the congo red and methylene blue dyes reached 75.5% and 90.57%, respectively, which exhibited different adsorption mechanisms, corresponding to the first-order and the second-order kinetic models, respectively, showing promising adsorption properties of distiller's grain CNCs on ionic dyes, and providing a low-cost and efficient way for the sustainable application of distiller's grain CNCs in the field of industrial wastewater treatment.

As an important part of straw, cellulose is the key to determine its mechanical strength. If applied to asphalt pavement, it is expected to improve the performance of the pavement and solve the problems of straw degradation and aging in the pavement. Firstly, the central composite design-response surface method was used to explore the influence of the extraction process of cellulose in straw on the performance of asphalt, and the optimum extraction process of cellulose was determined. Secondly, the effects of cellulose on high temperature stability, low temperature crack resistance and storage stability of asphalt were studied by rheological property test, segregation test and infrared spectrum test. The results show that the cellulose extracted under the condition of NaOH concentration of 2.5% and HNO₃ concentration of 4.3% has the best effect on improving the physical properties of asphalt. At the same time, the incorporation of corn straw cellulose improves the high temperature stability, low temperature crack resistance and deformation resistance of asphalt under high-speed vehicle load shear. When the content of corn straw cellulose is 7%, the comprehensive performance of asphalt is the best, and there is no serious segregation phenomenon. Compared with matrix asphalt, the high temperature continuous grading temperature (T_LH) of cellulose content at 7% is increased by 13 °C, and the low temperature performance is increased by 49.3%. In addition, cellulose only bonded with each other by physical enhancement to improve the performance of asphalt, and no chemical reaction occurred.

Cellulose is one of the most abundant resources in nature. The third-generation aerogels prepared from cellulose have both the high porosity and large specific surface area of traditional aerogels and their own advantages. However, its inherent flammability, poor mechanical properties and low thermal stability limit its application. At present, the functionalization of cellulose aerogels and the development of a variety of functionalized composite aerogels have become a research hotspot. In this paper, the preparation process, functionalization methods and main application fields of cellulose aerogels are summarized. Finally, the problems of functional cellulose aerogels are discussed.

In this study, bacteria cellulose/zeolite imidazole framework-8 (BC/ZIF-8) composite fiber membrane was prepared by one-step vacuum filtration method using zeolite imidazole framework-8 and bacterial cellulose as carrier. The structure of the composite fiber membrane was characterized by FT-IR, XRD, SEM, EDS and BET techniques. The effects of contact time, temperature, ion concentration and initial substrate concentration on the adsorption of tetracycline hydrochloride (TC) on the composite fiber membrane were investigated. The results showed that the BC/ZIF-8 composite fiber membrane had a richer pore structure than the BC membrane, and the specific surface area increased from 6.2415 m²/g to 265.8820 m²/g. The adsorption experiment shows that the ion concentration has insignificant effect on adsorption, and the adsorption process follows the quasi second-order kinetic model and Langmuir isotherm adsorption model. The adsorption of TC on the BC/ZIF-8 composite fiber membrane was mainly in the form of monolayer adsorption, with a theoretical maximum adsorption capacity of 438.59 mg/g.

As the material basis for the survival of life, fresh water resources are facing serious challenges. Using efficient solar-driven interface evaporation (SSG) is an important means to solve the current water shortage. A new porous material conjugated microporous polymer (CMPs) plays an important role in water treatment technology. A new type of solar energy evaporator (CMC/ SCMP-PPY) was prepared by spraying polypyrrole on its surface with CMC/SCMP as a precursor. The light absorption rate was up to 91% and the photothermal conversion ability was realized. The aerogel showed good photothermal conversion performance under 1 kW/m² irradiation, and the evaporation efficiency reached 85.57%. The porous structure and hydrophilic characteristics make it have excellent water transport ability, and the stable chemical structure makes it have excellent salt resistance to prevent salt crystal deposition and clogging material channels, so that it can realize the photothermal conversion ability. This work further optimizes the purification of CMPs in wastewater, realizes the utilization of clean energy, and provides a new idea for the development of new photothermal materials.

Biomass-derived carbon materials have attracted more and more attention as efficient and cheap supercapacitor electrode materials due to their renewability and flexible microstructure tunability. However, the original biomass-derived carbon has the disadvantages of low porosity, low specific surface area and insufficient specific capacitance. The specific surface area, pore structure and conductivity of electrode materials will affect the energy storage performance of supercapacitors. Therefore, how to fabricate electrode materials with high specific capacitance, fast charge and discharge and certain flexibility has become the focus of current research. In this paper, the classification and energy storage mechanism of supercapacitors and the preparation methods and research status of biomass-based carbon materials are reviewed. The key performance evaluation parameters of high-quality load electrodes are analyzed, and the influencing factors of their electrochemical performance are systematically discussed. The future development trend is to integrate different types of energy storage devices into composite energy storage devices to meet the needs of various fields. Composite energy storage devices have greatly improved the comprehensive performance of supercapacitors. Therefore, the development of efficient and stable energy storage technology is of great significance for alleviating energy shortage, reducing environmental pollution and promoting sustainable development.

With the development of modern industry, heavy metal water pollution has become one of the most important environmental problems. Heavy metal ions are highly toxic and difficult to degrade, being harmful to humans, aquatic animals, and plants to a large extent and damaging ecosystems. The advantages of low cost, high removal efficiency and recyclability of the adsorption method make it one of the important methods of wastewater treatment. Biomass materials are rich in resources, low cost, green and environmentally friendly, and have been widely studied as new adsorbent raw materials. Based on this, taking metal-organic framework, zeolite and biochar biomass materials as examples, this paper first reviews the preparation and modification methods of biomass matrix composites and summarizes the influence of the properties of adsorbents on metal ion adsorption, secondly elaborates the adsorption mechanism between them and metal ions, and finally puts forward the prospect of biomass matrix composites in the development of water pollution control.

Biomass is an excellent carbon source with abundant production, wide variety, low price and environmentally friendly, and the preparation of carbon catalytic materials from biomass is undoubtedly turning waste into treasure, which can fundamentally solve the problems of environmental pollution and resource waste. This paper introduces the effects of biomass species, components and structure on the performance of biomass carbon-based catalytic materials, compares the two common methods of pyrolysis and hydrothermal carbonization for the preparation of biomass carbon-based catalytic materials, discusses the three ways to further enhance the catalyst activity, heteroatom doping, metal-ion modification, and functionalization, and analyzes and summarizes the challenges faced by biomass carbon-based catalytic materials.

In this paper, a green carboxymethylcellulose sodium (CMC)/gelatin (GL)-glutaraldehyde (GA) composite aerogel (CL-A) was prepared by using the principle of chemical cross-linking and freeze-drying technology. The effects of different proportions of carboxymethylcellulose sodium (CMC), gelatin (GL) and different contents of glutaraldehyde (GA) on the microstructure, thermal stability, mechanical strength and thermal insulation and thermal insulation properties of the aerogel were investigated. The experimental results obtained after trying different raw material ratios showed that the compression modulus of the composite aerogel (C₁L₂-A₁₅) with the ratio of sodium carboxymethyl cellulose (CMC) to gelatin (GL) of 1:2 and the addition of glutaraldehyde (GA) of 15% is the highest of 3.03 Mpa, which is 7 times higher than that of pure sodium carboxymethyl cellulose (CMC) aerogel, and the mechanical properties have been enhanced effectively. The thermal conductivity of composite aerogel (C₁L₂-A₁₅) is the lowest, which is as low as 0.022 W/(m·k) with a better heat preservation effect. At the same time, the composite aerogel (C₁L₂-A₁₅) has a denser porous three-dimensional network, which improves the morphology of the composite aerogel to a certain degree. Lastly, the composite aerogel (C₁L₂-A₁₅) has up to 37% residual carbon, which improves the thermal stability to some extent. In summary, the compression modulus, microstructure, thermal stability, and thermal insulation properties of the composite aerogel (C₁L₂-A₁₅) after the addition of gelatin (GL) and glutaraldehyde (GA) are improved.

Using carboxymethyl cellulose sodium and polyethylene glycol as raw materials, a porous network structure was formed through cross-linking and gel, and a pH responsive gel membrane was prepared. The sample obtained antibacterial properties by soaked in tannic acid solution, and the microstructure, swelling properties, in vitro drug release, antioxidant properties, and antibacterial properties of the antibacterial membrane were characterized. The results show that the prepared antibacterial membrane has a good porous structure. The carboxyl group on carboxymethyl cellulose sodium endows the antibacterial membrane with certain pH responsiveness, which makes it exhibit anisotropic swelling and drug release in vitro at different pH values. After drug loading, the antioxidant capacity of the sample increases to 91.33%, and the antibacterial rate against Escherichia coli and Staphylococcus aureus reaches more than 90%. This antibacterial film has great application prospects in drug sustained-release dressings and other fields.

The microcrystalline cellulose/thermoplastic starch (MCC/TPS) film was prepared by melt extrusion method, and the MCC/TPS film was combined with paper by hot pressing method. The results show that the SEM images show that the interface layer of paper-plastic composite has good adhesion. When the addition amount of MCC is 5wt%, the mechanical properties of TPS film are improved, and the path of water vapor through TPS film is extended, resulting in the water vapor transmittability of MCC/TPS/paper composite is reduced, and the barrier properties of paper-plastic composite are improved. TPS/paper composites and MCC/TPS/paper composites have better physical properties (i.e. smoothness, flexibility and folding resistance) than paper alone. Therefore, the addition of MCC can improve the barrier properties and mechanical properties of paper-plastic composite materials to meet the requirements of the food packaging industry for low water sensitive materials.

Cellulose was the most abundant biological molecule in nature, as a major component of plant cell wall. Nanocellulose isolated through disintegration of cellulose fibers could be used as an adsorbent for wastewater treatment due to its excellent properties. Owing to its high cellulose content and almost without lignin in the cell walls, Chlorella was a good raw material for preparing nanocellulose. In this study, Chlorella-residual based TEMPO-oxidized cellulose nanofibers (TCNF) were prepared through TEMPO-mediated oxidation processes under gentle mixing without high-energy mechanical treatments. The average diameter of TCNF is about 2 nm, whereas its average length was about 300 nm, and the carboxyl content is 1.54 mmol/g. Moreover, methylene blue (MB) was used as a model dye to measure the adsorption capacity of TCNF. The adsorption capacity is almost saturated when TCNF contacted MB for 80 min, and the adsorption kinetics coincide with the pseudo-secondary kinetics model. The adsorption of TCNF on MB is greatly affected by the pH value, with a maximum value at pH = 8. The initial concentration of MB considerably affects its adsorption on TCNF. Below the initial concentration of 10 mg/g, adsorption of TCNF considerably increases with the increase in the initial concentration of MB. And when the concentration is higher than 10 mg/L, the adsorption tends to be saturated. Based on the sorption isotherms analysis of TCNF, the Langmuir model fits best with the experimental data. Thus, TCNF surfaces are uniform and monolayer adsorption occurred. In conclusion, the preparation of TCNF from Chlorella-residual is a simple and promising scheme for the removal of cationic dyes from industrial wastewater.

In this paper, CoFe₂O₄/biomass carbon composites were prepared by one-pot hydrothermal and high-temperature calcination methods. The microscopic morphology, crystal structure and electromagnetic parameters of the material indicate that CoFe₂O₄ can be uniformly dispersed in the carbon base, and the presence of CoFe₂O₄ is conducive to the defective polarization of the biomass during the carbonization process, which is beneficial to the enhancement of the wave absorption properties of the material. Effective regulation of the electromagnetic parameters of the composite material by adjusting the content of CoFe₂O₄ to optimize its impedance matching performance. Experimental results show that the minimum reflection loss (reflection loss, RL) value of -48.0 dB and effective absorption bandwidth (effective absorption bandwidth, EAB) of 5.5 GHz were obtained at 2.0 mm thickness of CoFe₂O₄/C-3.0 composite.

Bionic skin can simulate human skin with the ability to perceive a variety of stimuli, and has a wide range of applications in medical monitoring, artificial intelligence and other fields. However, traditional electronic skin materials usually have problems such as low mechanical strength, poor adhesion performance, and loss of flexibility due to easy water loss, which limits its application in the field of electronics. In this paper, a polymer of dopamine-modified carboxymethyl cellulose (CMC-DA) was prepared based on mussel adhesin and sodium carboxymethyl cellulose, a derivative of natural polymer cellulose, and introduced into a zwitterionic polycarboxybetaine (PCB) hydrogel. When the substitution degree of CMC-DA catechol group is 6.8%, CD-PCB hydrogel has good adhesion performance, and can be adjusted by different CMC-DA substitution degrees. The mechanical properties of the hydrogel are greatly improved. On this basis, natural polymer material silk protein is added to enhance the moisturizing performance of hydrogel. CDP-SILK hydrogels are also bacteriostatic, and obtain good electrical conductivity under the penetrating network of metal ions. In general, the material has developed a well-biocompatible zwitterionic biomimetic skin, which has high moisturizing, high adhesion, good biodescriptability and high electrical conductivity, showing good prospects for flexible wearable devices in bioelectronic applications.

With the increasing application of nanocellulose materials, it is found that some nanocellulose composites can improve its overall performance and have low cost and wide sources. Nanocellulose materials such as subnanometer cellulose crystal (CNC), microcrystalline cellulose (MCC), nanocellulose (NFC), bacterial nanocellulose (BNC) and other materials are prepared by different methods. With the help of mechanical stretching, spinning, electric field, magnetic field and other methods, it is used to prepare directional alignment with high orientation and high performance. Nanocellulose materials with high strength and stiffness are used in textile industry, medical industry, optical devices and other fields. In this paper, these methods and materials are briefly discussed and the application characteristics of materials and methods are summarized.

Using silver nanowires prepared by polyol method as conductive filler and kapok micro-fibrillated cellulose as carrier, the composite paper was prepared by vacuum filtration. The samples were characterized by scanning electron microscopy, X-ray diffractometer, X-ray photoelectron spectrometer, four-probe tester and vector network analyzer, and the effects of silver nanowire content on their electrical conductivity and electromagnetic interference shielding effectiveness were investigated. The results showed that the silver nanowires as one kind of one-dimensional silver elemental nanomaterial, were uniformly distributed in the composite paper and formed an excellent conductive network. When 2.5wt% of silver nanowires were added to the pure cellulose paper, the electrical resistance of the paper dropped from 470.57 MΩ·cm to 1.26 mΩ·cm. When the concentration of silver nanowires was increased from 2.5wt% to 10wt%, the conductivity of the paper increased from 793.65 S/cm to 3039.51 S/cm, and the electromagnetic interference shielding effectiveness increased from 38.1 dB to 61.5 dB.

Nanocellulose is widely used as water treatment materials because of their high surface area and aspect ratio, environmental biodegradability and renewability. Chlorella grows fast and its cell wall is rich in cellulose without lignin. High quality cellulose can be obtained by simple purification. In the present work, cellulose nanofibers (CNF) were prepared from chlorella waste by homogenization, with average diameter and length of 4.1±2.3 nm and 375±35.3 nm. The physicochemical properties of the prepared CNFS were determined by various techniques, and its adsorption performance was evaluated using methylene blue trihydrate (MB) and congo red (CR) as the model dyes. Results reported in this study indicate that the adsorption of MB and CR on the CNFS follow pseudo-first-order kinetics and the pseudo-second-order. Besides, the effects of pH and dye concentrate on adsorption were also investigated. Further analysis reveals that the process of MB and CR adsorption follow the Langmuir isotherm model. The maximum capacity of cationic MB dye adsorption on the CNF is 161.25 mg/g, and anionic CR dye adsorption is 181.36 mg/g. The pH has a significant effect on the adsorption capacity of CNFS, which have maximum adsorption capacity the maximum adsorption capacity. But for CR, the lower the pH, the stronger the adsorption capacity is, in the pH range of 5 to 10.

Cellulose has the characteristics of renewable, degradable, environmental, pollution-free, etc. Using celluloses as raw materials, the prepared cellulose-based membrane material shows excellent properties of separation, adsorption, conduction, magnetic and stimulus-response, and is widely used in separation, conduction, packaging, adsorption, and other research fields. In this paper, the application of cellulosic materials in the fields of separation film, conductive film, packaging film, and adsorption film was reviewed, and its future development trend was prospected.

Highland barley straw ash (HBSA) prepared by calcination and grinding under certain conditions is an active admixture of biomass silicon source, which will affect the mechanical properties of magnesium oxychloride cement (MOC). In order to study the influence of HBSA added into MOC on its mechanical properties, MOC mortar specimens with different HBSA content were tested for flexural and compressive strength under dry and saturated conditions respectively. Strength loss rate and softening coefficient were used to characterize the degree of mechanical property damage of MOC in saturated conditions. The pore structure of MOC mortar specimens was tested and characterized by low field nuclear magnetic resonance technology and gas adsorption method. The results show that MOC with 5% HBSA has the highest flexural and compressive strength in dry and saturated conditions, while MOC with 10% HBSA has the lowest strength loss rate and the highest softening coefficient in saturated conditions. When the content of HBSA is 10%, the proportion of harmful pores and multi harmful pores in the pore structure of MOC is significantly reduced, and the most probable pore diameter is reduced, which optimizes the pore structure of MOC and enhances the mechanical properties in saturated conditions.

By adding different biomass (corn cob or pine sawdust) to hypercoal, the activated carbon electrode materials for double electric layer capacitors were prepared. The effect of biomass on the structure and electrochemical performance of hypercoal-based activated carbon was explored. Its structure and composition were characterized by SEM, XRD, FTIR and N₂ desorption. Its electrochemical performance was tested by cyclic voltammetry, constant current charge-discharge and AC impedance. In terms of biomass composition, the addition of biomass with high cellulose content is beneficial to the development of mesopore and the pore structure is more perfect. High cellulose and hemicellulose content can effectively reduce the impedance of carbon materials, and make the ion transport between pore structures more rapid. When corn cob was added to hypercoal, the specific capacitance increased by 45% and the charge transfer resistance decreased by 65%. Adding pine sawdust to hypercoal can increase the specific capacitance by 30% and decrease the charge transfer resistance by 35%. It is proved that adding biomass with high cellulose content is more beneficial to improve the structure and electrochemical performance of activated carbon.

China is rich in agricultural and forestry biomass resources, but the low utilization rate results in great waste. With the depletion of petrochemical resources, biomass materials have increasingly attracted attention. Various biomass substitutes have been gradually explored and studied, and more kinds of green environmentally friendly foam materials are widely used because of their lightweight and excellent nature. This paper mainly introduces the preparation of foam materials by replacing non-renewable petroleum resources with biomass materials (starch, lignin, cellulose, vegetable oil, tannin), and summarizes the main foaming mechanism, research progress and potential application fields of various types of foams.

It is difficult to separate ordinary biochar from water environment, and it may cause secondary pollution, which hinders the large-scale application of ordinary biomass charcoal as adsorbent. An effective strategy to address this problem is to introduce transition metals and their oxides into the biochar matrix, resulting in easily separated magnetic biochars. Magnetic biochar can not only effectively remove heavy metal pollutants in aqueous solution, but also realize the separation of magnetic adsorbents by applying an external magnetic field, and then recover-regenerate-reuse to improve its repair performance. Due to its superiority in heavy metal adsorption, it has attracted extensive attention and research in the field of heavy metal-contaminated water treatment. The review briefly summarizes the different preparation methods of magnetic biochar, sorts out the mechanism of magnetic biochar adsorption of heavy metals, and analyzes the factors affecting the interaction between magnetic biochar and heavy metals. Finally, the further research needs and future research directions of magnetic biomass char in the treatment of heavy metal polluted water are pointed out, and the future development prospects and potentials are prospected.

Cellulose nanocrystals (CNCs) is a natural polymer material with renewable and degradable properties. In this current study, based on the outstanding physical properties of graphene oxide (GO), CNCs-GO highly ordered layered structures are prepared by vacuum filtration method to improve the mechanical strength and hydrophobic properties of CNCs films. The experimental results show that when the mass fraction of graphene is 4%, the tensile strength of CNCs-GO layered film reaches a maximum of 204.4 MPa, which is 58.8% higher than that of the original CNCs film. The elastic modulus of layered films increases first and then decreases with the increase of GO mass fraction. The accuracy of mechanical test results is verified by analyzing the microstructure and dynamic thermo-mechanical properties of layered films. The contact angles of CNCs films and CNCs-GO layered films are measured, and it is found that the hydrophobic properties of the layered films are significantly improved due to the interaction between the hydrogen bond network of CNCs and the free hydroxyl groups on the GO surface.

The use of green renewable cellulose nanocrystals (CNCs) with the ability to self-assemble photonic structures to construct flexible functional materials can provide rich visual information, reduce the cost and reduce the harm of non-degradable materials. However, due to the lack of effective soft energy consumption phase in the system, the photonic materials based on CNCs have shortcomings such as mechanical fragility and lack of dynamic optical response, which bring certain challenges to their functional expansion and application. Thus, according to the structural characteristics of CNCs, this paper introduces in detail the preparation methods and influencing factors of the current CNCs photonic membrane, and then summarizes the various synthesis and regulation strategies of the current CNCs photonic membrane from mechanical rigidity to mechanical flexibility and machine color responsiveness. At the same time, the promising application directions and future challenges of CNCs flexible functional photonic materials are emphasized in this paper.

The work aims to explore the effects of microcrystalline cellulose/gelatin on heat sealing, mechanics and thermal stability performance of starch composite films with a view to improving the comprehensive properties of starch-based films. In this study, microcrystalline cellulose/gelatin (MCC/GL) was used as enhancement phase to prepare microcrystalline cellulose/gelatin/starch film (MCC/GL/ST) by solution casting method. Scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and thermo gravimetric analysis (TG) were used to analyze the films of apparent morphology and thermal stability, and the mechanical properties and heat sealing properties of starch films were characterized by heat sealing instrument and universal material tension. The result shows that compared with that of microcrystalline cellulose/starch film (MCC/ST), in microcrystalline cellulose/gelatin (2∶8)/starch film (MCC/GL/ST-2), heat sealing strength was increased by 352.9% and tensile strength was increased to 9.12 MPa. Infrared spectroscopy (FTIR) shows that there is a hydrogen bond interaction between MCC and GL, and the film barrier performance improves with the decrease of gelatin addition. The DSC and TG curves show that MCC/GL/ST-2 has good thermal stability, which can meet the heat sealing processability and ensure its stable performance.

A novel KOH-Fe/Zn biochar (KOH-Fe/Zn-BC) was prepared for tetracycline removal using KOH activation and Fe/Zn modification. The chemical, morphological and structural characteristics of the biochar were characterized using FTIR, SEM-EDS, N₂ adsorption isotherms and XPS. EDS images showed that comparing the elemental distribution on the surface of the material before and after adsorption, the elemental content of Si, Fe and Zn decreased, which was consistent with the results of XPS analysis that these elements interacted with TC molecules. BET results showed that KOH-Fe/Zn-BC reached a specific surface area of 191.47 m²/g. The adsorbent formed a pseudo-secondary kinetic and Langmuir isotherm adsorption process even under the interference of external ions and pH. The adsorption mechanism of KOH-Fe/Zn-BC was evaluated and attributed to the synergistic effects of electrostatic attraction, hydrogen bonding interactions, and physical and chemical adsorption. The results of the study provide a theoretical basis for the removal of tetracycline from water by municipal sludge biochar.

Aerogels have the characteristics of low density, high specific surface area, high porosity, etc., and have broad application prospects in the field of water pollution treatment. CNC/CS aerogels with good aqueous solution stability were prepared by freeze-drying and solid-phase cross-linking technology using natural green polymer materials cellulose nanocrystalline (CNC) and chitosan (CS) as raw materials. Scanning electron microscope (SEM) was used to characterize the appearance of the aerogel, and the adsorption performance of the aerogel to hexavalent chromium ion (Cr(Ⅵ)) in water was investigated by spectrophotometry, and the adsorption results were simulated by pseudo first and second order kinetic fitting. The results showed that the aerogel with 50% CNC content had the best water stability, and the mass residual ratio after shaking for 48 h in deionized water reached 93.8%. The aerogels presented rich honeycomb pore structure, and the adsorption capacity for Cr(Ⅵ) reached up to 67.377 mg/g, and it had a fast adsorption rate for Cr(Ⅵ). When the concentration of Cr(Ⅵ) solution was lower than 60 mg/L, the adsorption equilibrium can be reached within 24 h. The adsorption kinetic fitting results showed that the adsorption behavior of CNC(50%)/CS aerogel to Cr(Ⅵ) conformed to the pseudo second order adsorption kinetic model, indicating that the adsorption process was dominated by chemical adsorption.

The separator is an essential part restricting the development of high-performance lithium-ion batteries. High-performance cellulose separators with biodegradability and electrolyte affinity are promising. However, the strong hydrogen bonding between cellulose nanofibers usually leads to the formation of dense membranes rather than ideal porous membranes. In this paper, a different strategy is suggested to prepare a CF&SiO₂ separator with a core-shell structure by regulating the morphology of bacterial cellulose (CF&SiO₂) composite separators by chemical foaming combined with nano-silica particles hybridization. The CF&SiO₂ separator has excellent thermal stability (200 ℃) and high ionic conductivity of 1.44 mS/cm. The coin-cell battery is assembled from LiFePO₄ cathode and Li anode exhibited superior cycling stability at 5 C, holding a high specific capacity of 124.7 mAh/g after 300 cycles.

In view of the advantages of cellulose and its various applications, how to obtain cellulose from biomass and make it into a configuration that fits the target application scenario is of great importance. Firstly, the extraction methods of cellulose were summarized, including acid-alkali, ozonolysis, ionic liquids, deep eutectic solvents, organic solvent, and steam explosion. The pros and cons of these extraction methods were compared and analyzed. Secondly, the preparation methods of fibrous membranes were elaborated, including electrospinning, melt spinning and wet spinning. The electrospinning, a simple and cheap technique, is considered to be a commonly used method. More importantly, nanoscale fibers with high specific surface areas can be fabricated by this method and are expected to provide significant contributions to many properties and make a positive impact on the applications. In addition, these recent and excellent applications of fibrous membranes in substance separation, fabrics, photoelectricity and medicine were overviewed. Finally, the perspectives and challenges in cellulose extraction, fibrous membrane preparation and application were outlined.

With the interconnection of all things realizing, the demand amount for green, sustainable and high stability energy storage materials is increasing. Biomass-derived carbon has attracted more attention due to its rich pore structure, large specific surface area, environmental friendliness and considerable economic value. In this paper, the structure and synthesis methods of biomass-derived carbon were introduced, and the research status of biomass-derived carbon electrode materials was summarized. The new development trend and new challenges of biomass-derived carbon electrode materials were put forward, which provided ideas for future rational design of biomass-derived carbon energy storage materials.

Due to their excellent biocompatibility, renewability, degradability and high porosity, nanocellulose aerogels have broad application prospects in the field of building insulation. In order to better enhance the thermal insulation and mechanical properties of nanocellulose aerogels, a composite nanocellulose aerogel with regular pore structure was prepared by introducing polyimide. The structure and properties of the composite aerogels were fully characterized by SEM, thermal conductivity tester and infrared imager and other testing meters. The results showed that when the mass ratio of CNF:PI was 1:1, the structure and pore size of the composite aerogels were the smallest, and the diameter of the composite aerogels was 15-18 μm, the density is as low as 0.0413 g/cm³, the compressive strength is up to 0.33 MPa, and the thermal conductivity is as low as 0.03159 W/(m·K), showing the most excellent comprehensive performance.

Biomass porous carbon with a wide range of raw material sources and green and eco-friendly has received extensive attention. In this manucript, the imperata cylindrica has successfully developed as a precursor of a new type of biomass porous carbon. With KOH as an activator and urea as a dopant nitrogen-doped porous carbon materials was formed by one-step pyrolysis and carbonization. And then we investigated the optimal doping ratio of urea. The prepared materials were characterized by SEM, TEM, XRD, Raman and XPS. The electrochemical performance of the material was tested by the three-electrode system. The results showed that the prepared electrode material had the best performance when the mass ratio of 2:1. In 6 mol/L KOH electrolyte, when the current density is 1 A/g, the specific capacitance of the material is 304.1 F/g. After 5000 long cycles, the capacity retention rate is 96.24%.

The work aims to prepare the superhydrophobic coatings with excellent self-cleaning performance and good durability by a simple dip-coating.The superhydrophobic coatings were prepared based on cellulose nanofibers (CNF) and low surface energy polydimethylsiloxane(PDMS) to achieve the surface functionalization of cotton fabrics. The effect of different contents of polydimethylsiloxane and CNF on hydrophobicity of coatings was studied by single factor experiments. And the superhydrophobic coatings were characterized by Fourier transform infrared spectrometer(FT-IR), scanning electron microscope(SEM) and thermal gravimetric analyze(TGA). The results showed that durable superhydrophobic coatings were successfully prepared by cellulose nanofibers and polydimethylsiloxane. The SEM results showed that CNF constructed the microrough structure required for the superhydrophobic coating as compared to the pure PDMS coating, and provided favorable conditions for the preparation of the superhydrophobic coatings. With 4wt% PDMS and 4wt% CNF, the superhydrophobic coating showed water contact angle of 159.2°, and the water sliding angle of 4.3°. The results showed that the water contact angle of superhydrophobic coating still kept 150.3° even after 40 cycles of sandpaper friction, and it still had superhydrophobic performance. It was indicated that the polydimethylsiloxane provided low surface energy for the coatings, and had good bonding performance which improved the coatings' durability. In conclusion, a durable superhydrophobic coating was successfully prepared on cotton fabric surfaces with CNF and PDMS, while achieving excellent self-cleaning, waterproof and pollution resistance performance and good durability.

Cellulose aerogel (CA) can be used as ideal substrate for hybrid nanocomposite owing to their unique three-dimensional layered network structure, abundant porosity and large specific surface area. However, cellulose aerogel materials are prone to structural crumple during the solvent exchange and drying processes due to plenty of hydrophilic hydroxyl on the molecular chains, which reduces their mechanical properties and limits their broad applications. Metal-organic framework (MOF) materials are an emerging class of inorganic-organic hybrid porous, which have attracted great interest because of their unique advantages, such as structural diversity, homogeneous and controllable pore size. In recent years, researchers have utilized the intrinsic structure and functional properties of cellulose aerogel as a new carrier to incorporating MOF reinforced phase into the porous network of CA, which fabricates novel functional hybrid nanocomposite. Until now, related basic research is gradually expanding and showing greater potential for application. Herein, this review focuses on discussing the preparation strategies, composition optimization, structural design of novel MOF/CA hybrids, and their applications such as flame retardant performance, separation/adsorption, electromagnetic shielding, etc. Future prospects in synthesis techniques and applications are provided to address opportunities and challenges in this field.