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Microfibrillated cellulose (MFC) as an attractive green bio-based material has attracted widespread attention in recent years due to its non-toxicity, degradability, excellent performance, and high aspect ratio. In this study, the g-C 3 N 5 with a high nitrogen/carbon ratio was prepared as a catalyst through the self-polymerization of a nitrogen-rich precursor. The triazole groups at the edges of g-C 3 N 5 were proven to exhibit strong adsorption to biomass and strong alkalinity. In a low-acidic aqueous system with g-C 3 N 5 , MFC with diameters of 100-200 nm and lengths up to 100 μm was fabricated from various biomasses within 5 min under microwave radiation. The ultimate yield of the MFC produced from viscose reached 90 %. Young's modulus of the MFC reaches 3.7 GPa. This work provides a particular method with high efficiency to prepare MFC with excellent properties from biomass by chemical method., 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 B.V. All rights reserved.)

Herein, a novel cellulose-based fluorescent material with amine-responsive property was developed in a CO 2 switchable solvent for the contactless, real-time, and visual monitoring of the freshness of shrimp, crab, and fish. A nucleophilic cellulose carbonate intermediate is in-situ formed upon dissolution of cellulose in the CO 2 switchable solvent, which is adopted for the highly effective grafting of poly(l-lactic acid) and amine-responsive fluorescent reagent 7-amino-4-(trifluoromethyl) coumarin onto the cellulose backbone via ring opening polymerization and nucleophilic substitution reaction, respectively. The product has good processibility, and sensitive and reversible fluorescent responsive towards ammonia. The fluorescent intensity of the material decreased significantly and its fluorescent color changed from blue to cyan, when the aquatic products got spoiled. This study indicates that the CO 2 switchable solvent has great potential for the modification of cellulose with various functionality by taking advantage of the highly active nucleophilic cellulose carbonate intermediate., 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 © 2022 Elsevier Ltd. All rights reserved.)

In this work, hydroxyl-enriched glucose-based carbonaceous sphere (HEGCS) is prepared by hydrothermal method as an accelerator to enhance the hydrolytic efficiency of the treated cellulose to sugar in low-acidic aqueous system under microwave radiation. Due to the strong affinity of HEGCS to cellulose, during the hydrolysis, the treated cellulose can be flaked into small fragments by HEGCS, which is like a "microball milling", and accordingly, the hydrolytic accessibility of cellulose is extremely improved. Highly efficient hydrolysis of cellulose to sugar is finally achieved in HEGCS containing 0.02 mol/L sulfuric acid. One hundred percent conversion of cellulose and 96.0 ± 4.0% total reducing sugar (TRS) yield was obtained within 15 min under microwave radiation. The average content of glucose in sugar products is over 70%. Our research not only obtains a catalytic accelerator to establish an effective method for hydrolyzing treated cellulose to sugar but also provides the idea for regulating cellulose accessibility during hydrolysis to achieve high efficiency in the hydrolysis of cellulose.

The native Cellulose-AgCl fiber have been firstly fabricated by one-step electrospinning of cellulose solution with poly(vinyl pyrrolidone) (PVP) and AgNO 3 . X-ray diffraction, Scanning electron microscopy (SEM), Energy dispersive spectrometer, Thermo-gravimetric analysis and Fourier transform infrared are used to characterize the crystal structure, morphology and composition of cellulose-AgCl nanocomposites. The results of SEM indicate that the size of AgCl in cellulose fiber matrix is able to be adjusted by the addition of Polyvinylpyrrolidone (PVP). The antimicrobial activity of the nanocomposites fiber is also tested against the model microbes E. coli (Gram-negative) and S. aureus (Gram-positive). The results indicate that cellulose-AgCl nanocomposites have a good antimicrobial activity, which is improving with the decrease of AgCl size in fiber matrix. This work provides a novel and simple way to adjust the AgCl size in electrospinning cellulose matrix which can be applied as functional biomaterials.

This work studied the hydrolysis behavior of regenerated celluloses (RCs) with different degree of polymerization (DP) by using the catalyst of dilute acid under microwave radiation. Results showed that the DP had a considerable influence on hydrolysis of cellulose. The reactivity of RCs was significantly improved when DP was lower than 51. The highest sugar yield of 59.2% was achieved from RC with lowest DP of 23 at 160 °C for 15 min. But the lowest yield of 32.6% was obtained when RC with highest DP of 132 was used. Recrystallization of cellulose was found to hinder the further hydrolysis particularly with the high DP. The effect of recrystallization can be reduced by the decrease of DP of RCs. This research demonstrates that the DP of RCs plays a crucial role on hydrolysis and it provides a preliminary guide based on DP to find a suitable pretreatment method for cellulose hydrolysis., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Water and four small molecular alcohols are respectively used to activate corn cellulose (CN cellulose) with the aim to improve the dissolvability in DMAc/LiCl. Among all these activated agents, monohydric alcohols are found to produce the optimal effect of activation in the whole process including of activating, dissolving, and electrospinning of CN cellulose. Meanwhile, well distributed fibers with the diameter of 500nm-2μm are fabricated in electrospinning. Understanding the activation effect of monohydric alcohols with water and polyhydric alcohols, the most effective activated agent is ascertained with the characteristics of small molecular size, low viscosity, and single functionality. This work is definitely initiated to understand the critical principle of CN cellulose in dissolving. Accordingly, a feasible methodology is also established to prepare ultrafine cellulose fibers with good morphology in electrospinning., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

This work studied the responsive behavior of regenerated cellulose (RC) in hydrolysis under microwave radiation. Four types of RC with different crystallinity (Cr) and degree of polymerization (DP) are produced to evaluate the reactivity of RC by step-by-step hydrolysis. Results show Cr is the key factor to affect the reactivity of RCs. With hydrolysis of amorphous region and the formation of recrystallization, the Cr of RC reaches a high value and thus weakens the reactivity. As a result, the increment of cellulose conversion and sugar yield gradually reduces. Decrease of the DP of RC is helpful to increase the speed at the onset of hydrolysis and produce high sugar yield. But, there is no direct influence with the reactivity of RC to prolong the time of pretreatment. This research provides an accurate understanding to guide the RC preparation for sugar formation with relative high efficiency under mild reaction conditions., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

A two-step acid-catalyzed hydrolysis methodology is established to effectively hydrolyze cellulose to glucose with high yield and selectivity under mild conditions. In multi-steps hydrolysis, the difficulty of cellulose can be effectively reduced under mild conditions. In the first step, microcrystalline cellulose was depolymerized in phosphoric acid to cellulose oligomer at 50°C. Then the oligomer was precipitated by ethanol and hydrolyzed with dilute sulfuric acid in the second step. 87.7% total reducing sugars and 57.8% glucose was released from the two-step hydrolysis process. In addition, with the assistance of microwave in the second step, the yield and selectivity of glucose can be improved to 73.3% and 80.1% by only 5 min hydrolysis. The two-step hydrolysis exhibits an effective process to produce glucose in cellulose hydrolysis. The enhancement of hydrolysis reactivity is considered to be controlled with the decrease of crystallinity and degree of depolymerization of cellulose., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Regenerated cellulose/poly (vinylidene fluoride) (PVDF) blend film was successfully prepared through coagulating their N,N-dimethyl acetamide (DMAC)/LiCl solution with water. The toughness of the blend films, compared with virgin regenerated cellulose film, was significantly improved when the content of PVDF in blend films was no more than 20 wt.%. The elongation at break increased from 12% to 34%, and the tensile strength was also improved from 89 to 106 MPa with the addition of PVDF till 20 wt.%. The mechanical properties of the blend films became worse when the content of PVDF in blend films was more than 20%. The oxygen permeability was firstly decreased from 2.3 1 (-10) to 0.036 1 (-10)cm(3)cm/cm(2)s Pa when the PVDF content increased from 0 to 5 wt.% in the blend films. Afterwards, the oxygen permeability would increase with the increasing of the PVDF content. The film showed some pores when the loading level of PVDF was more than 50%. The pore size of blend film became larger with the increasing of PVDF content. These phenomena were well correlated to the crystallinity, hydrogen bonds and morphologies of the blend films., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Pyruvaldehyde as a carbon source is synthesized together with boric acid to produce a carbon-based solid catalyst with in situ bifunctional groups of adsorptive boron hydroxyls and carboxyls in a single-step hydrothermal carbonization process, which is mainly utilized to induce the hydrolysis of cellulose to sugar in pure water. The obtained catalyst exhibits a strong adsorption capacity of 532 mg g−1 with cotton cellulose and possesses good water dispersibility. It can effectively break the aggregated structure of cellulose through the strong interfacial adsorption interaction to induce the hydrolysis of cellulose to sugar with high efficiency in the pure aqueous system. The cellulose conversion and the glucose yield reach 97.3% and 40.0%, respectively. Additionally, the catalyst demonstrates excellent hydrothermal stability and reusability. As a result, a high-yield, acid-free, green, and environmentally friendly hydrolytic process of cellulose to sugar in pure water is successfully established. [ABSTRACT FROM AUTHOR]

The development of highly efficient and environmentally friendly solvents for dissolving cellulose, which is the most abundant natural polymer on Earth, remains a challenge, hindering its full utilization. Herein, a green protic ionic liquid, 1,1,3,3-tetramethylguanidinium methoxyacetate ([TMGH][MAA]), was found to exhibit attractive capacity to dissolve natural cellulose with an appropriate TMG/MAA molar ratio of 7 : 3 at 80 °C. The solubility of cotton linter and ultra-high molecular weight cotton fibers reached 13% (w/w) and 3% (w/w), respectively, surpassing that of most solvent systems currently used for the dissolution of cellulose. The experimental and simulation results verified that the excellent dissolution ability of [TMGH][MAA] for cellulose is mainly attributed to the destruction of the intrinsic hydrogen-bond networks in cellulose by the synergistic interactions of the [TMGH] cations and [MAA] anions with the hydroxyl groups in the cellulose chains, acting as highly efficient "intermolecular scissors". The superiority of this novel dissolution system was further demonstrated by the remarkable comprehensive properties of the regenerated cellulose film including satisfactory thermostability, high transparency, and excellent mechanical properties. Furthermore, the satisfactory recovery performance of this solvent highlights its significant feasibility for large-scale industrial manufacturing. The proposed [TMGH][MAA] in this study exhibits great potential as a next-generation processing solvent for dissolving, and thus processing cellulose, promoting the sustainable development of high-value-added cellulose materials. [ABSTRACT FROM AUTHOR]

Fabrication of fluorescent cellulose with aggregation‐induced emission (AIE) characteristics is usually achieved by grafting tetraphenylethylene (TPE) to the cellulose backbone using TPE derivatives with highly active functional groups such as carboxylic, isothiocyanate, and alkynyl groups. However, besides the complicated synthetic routes of these TPE derivatives, conversion of hydroxyl groups in the cellulose chain to more reactive groups such as amine or azide groups is usually involved, and the resulting products have a degree of substitution (DS) of TPE lower than 0.08. Herein, a facile one‐pot strategy for the grafting of a TPE group to the cellulose backbone with high DS of up to 0.22 in a CO2 switchable solvent under mild reaction conditions is reported. The hydroxyl groups in the cellulose are in situ converted to cellulose carbonate intermediately during the dissolution step. Subsequently, nucleophilic substitution between the intermediate and a halogenated TPE derivative with bromine atom as leaving group is carried out to achieve the effective grafting of TPE. The synthetic route for this promising TPE derivative is much more convenient than those of TPE derivatives reported in previous studies. This work suggests a new and facile pathway for the synthesis of high‐emission fluorescent cellulose with AIE functionality. [ABSTRACT FROM AUTHOR]

Dye is an anionic common pollutant in industrial wastewater and poses a great threat to the environment and human health. Owing to its advantageous adsorption capacity, nanocellulose is widely used for wastewater treatment. The cell walls of Chlorella mainly comprise cellulose instead of lignin. In this study, residual Chlorella-based cellulose nanofiber (CNF) and cationic cellulose nanofiber (CCNF) with surface quaternization were prepared through homogenization. Moreover, Congo red (CR) was used as a model dye to measure the adsorption capacity of CNF and CCNF. The adsorption capacity was almost saturated when CNF and CCNF contacted CR for 100 min, and the adsorption kinetics coincided with the pseudo-secondary kinetics model. The initial concentration of CR considerably affected its adsorption on CNF and CCNF. Below the initial concentration of 40 mg/g, the adsorption on CNF and CCNF considerably increased with the increase in the initial concentration of CR. Based on the sorption isotherms analysis of CNF and CCNF, the Langmuir model fitted best with the experimental data. Thus, CNF and CCNF surfaces were uniform, and monolayer adsorption occurred. The adsorption of CR on CNF and CCNF was greatly affected by the pH value, and the acidic medium favored the adsorption of CR (especially for CCNF). CCNF showed a more advantageous adsorption capacity, with a maximum value of 1657.89 mg/g, compared to that of CNF (190.0 mg/g). According to the findings of this study, residual Chlorella-based CCNF could be a very promising adsorbent candidate for removing anionic dyes from wastewater. [ABSTRACT FROM AUTHOR]

Through analysis of the transformation of carbon sources including glucose, fructose, and 5-hydroxymethylfurfural in hydrothermal carbonization (HTC) and the adsorption of carbon tubes (CNTs) with them, the formation mechanism of a hydroxyl-rich carbon layer on the CNT surface is clearly revealed. During HTC, the adsorption of furan and aromatic clusters and even primary particles by CNTs by π–π interaction is noticed as the key condition to improve the utilization rate of carbon sources and the quality of the carbon layer. The coated CNTs own a hydroxyl-rich carbon layer with a thickness of several nanometers on its surface, which provides the ability for functional applications. With the use of the hydroxyl-rich carbon layer-coated CNTs, a low-acid aqueous system is established for the hydrolysis of cellulose to sugar. Accordingly, the cellulose conversion and glucose yield are obviously improved. The route of HTC for hydroxylation of CNTs not only fundamentally avoids the use of strong acid oxidation in traditional method but also provides the useful guidance to prepare functional carbon materials with application prospects. [ABSTRACT FROM AUTHOR]

Development of an anhydrous homogeneous method for the cyanoethylation of cellulose is highly desirable. In this study, a series of cyanoethyl cellulose (CEC) composites were homogeneously prepared via the Michael addition of acrylonitrile (AN) to the activated hydroxyl group of cellulose in a novel CO2 switchable solvent. The cellulose was dissolved in this solvent generating a nucleophilic cellulose carbonate intermediate, which is able to react with AN directly via Michael addition and results in CEC with a tunable degree of substitution (DS) by varying reaction conditions, such as temperature, reaction time, and the feeding ratio of acrylonitrile. The obtained CEC samples have DS values ranging from 0.12 to 1.03. The solubility of the CEC samples varies with DS values. This organic and anhydrous CO2 switchable solvent system enables the preparation of CEC with high quality without side reactions induced by water and much easier down-stream treatment, which is superior to other homogeneous counterparts. This study suggests a new platform for the synthesis of novel cellulose derivatives by Michael addition in the CO2 switchable solvent system in the future. [ABSTRACT FROM AUTHOR]

Cellulose-grafte-poly(L-lactide) (C-g-PLLA) copolymers synthesized in a CO2-switchable solvent are proposed for use as effective compatibilizers for the preparation of cellulose–PLLA composites with enhanced interfacial compatibility. The effect of the molar substitution (MSPLLA) of the grafted PLLA side chain in the C-g-PLLA copolymer and the feeding amount of this copolymer on the mechanical and thermal properties and hydrophilicity of the composites was investigated. The composites had a largely increased impact strength with the incorporation of the compatibilizer. With the increasing of MSPLLA and the feeding amount of the copolymer, the resulting composites had an increased impact strength. When 5 wt% C-g-PLLA with MSPLLA of 4.46 was used as a compatibilizer, the obtained composite containing 20 wt% cellulose presented an impact strength equal to that obtained for the neat PLLA. The composites had a slightly decreased melting temperature and thermal decomposition temperature, but increased hydrophilicity due to the incorporation of the compatibilizer. This work suggests an effective method to improve the interfacial compatibility between cellulose and PLLA for the fabrication of fully bio-based composites with high performance. [ABSTRACT FROM AUTHOR]

As it is a material obtained from natural resources, the functionalization and applications of cellulose have attracted interest recently. In this work, we reported a facile method for preparing bio-inspired functionalized corncob cellulose/rGO (CL/rGO) aerogels through freeze-drying technology. Measurements of the adsorption performance toward MB showed us that cellulose/rGO aerogels had good adsorption performance at pH = 7 and room temperature. In addition, we carried out adsorption–desorption cycling experiments to evaluate the stability and recyclability of CL/rGO aerogels. The good adsorption abilities endow the CL/rGO aerogels with great potential applications, e.g., they can be utilized for dye wastewater treatment. [ABSTRACT FROM AUTHOR]

Organic solvents with low Henry's constants, such as propylene carbonate (PC) and sulfolane, were proposed to be used as CO2 absorbents to increase CO2 absorption capacity in the CO2 switchable solvent, so that the dissolution of cellulose can be effectively enhanced. With the addition of PC, the maximum concentration achieved for the dissolution of paper cellulose can be largely increased from 1.0 to 5.0 wt%, while those for microcrystalline cellulose and corncob cellulose were increased from 5.0 to 10.0 and 7.0 wt%, respectively. Moreover, the chemical and crystalline structure of the regenerated cellulose was not affected by the addition of CO2 absorbents. This study illustrated a simple and effective way to modify the CO2 switchable solvent, which would be helpful for the application of the complex solvent system for the enhanced dissolution, derivatization, and processing of cellulose in the future. [ABSTRACT FROM AUTHOR]

Carbon aerogels (CAs) have been considered potential microwave absorption (MA) materials because of intrinsic hierarchical porous structure, low density, and excellent heat resistance. However, CAs always required to be ground into micron-scale powder before being used as microwave absorbers, which will inevitably destroy the hierarchical porous structure. Meanwhile, reproducing the optimized CAs powders is difficult. Herein, CAs microspheres with in-situ mineralized TiO2 were easily prepared via a sol-gel transition and calcination process. The uniform size of CA microspheres and the loaded TiO2 on the skeleton of CA yield great microwave attenuation performance while guaranteeing good impedance matching performance. The obtained TiO2/CA hybrid presented a minimum reflection loss value of −30.2 dB and a broad effective absorption bandwidth (reflection loss below −10 dB) of 6.2 GHz. The low density, MA performance, and controllable particle size make the novel TiO2/CA hybrid promising candidates for MA applications. [ABSTRACT FROM AUTHOR]

The hydrogel supported catalyst is explored as an efficient strategy for water remediation due to its combination of absorption and degradation, while it remains great challenge to prepare highly dispersed multi-component catalyst. Herein, cellulose-based hydrogel containing dual-component catalysts was fabricated via in-situ synthesis and mineralization, where the cellulose network containing –OH and –COOH provided a good platform for achieving highly dispersed TiO2 and Fe3O4. To the methylene blue (MB) solution (c0 = 20 mg/L), the TiO2/Fe3O4 nanocomposite hydrogel displayed a high removal ratio of 97.5% in 60 min by photo-Fenton reaction. Interestingly, owing to the ionic hydrogel feature, the degradation efficiency maintained over 97.2% in a broad initial pH range from 4 to 7, And the hydrogel could effectively hold the contaminants with nearly no leakage and retained the removal ratio of 98.0% after 5 degradation cycles. This study provides new insights into the in-situ synthesis of multi-component catalyst in hydrogels for efficient, stable, and safe water treatment. [ABSTRACT FROM AUTHOR]

A series of cellulose-based fluorescent materials are prepared under relative mild conditions by use of the DMSO/1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)/CO2 system to utilize as coating pigments. Through the observation under 365 nm UV light, the cellulose-based fluorescent materials exhibit good fluorescence response and bright color. Furthermore, due to the limitation of the molecular skeleton of cellulose, the intrinsic aggregation caused quenching phenomenon commonly existed in conventional organic fluorescent pigments can be effectively inhibited, which is very helpful to retain good fluorescence response in epoxy-based coating material and its coating films. Moreover, the addition of cellulose-based fluorescent materials also increases the mechanical properties of the coating film. The increase of tensile strength and tensile modulus respectively reaches ~39% and ~66%. Solvent resistance and thermal property of the coating films generally remain unchanged. The fabrication of cellulose-based fluorescent materials in DMSO/DBU/CO2 system provides a feasible way to develop the functional application of cellulose. [ABSTRACT FROM AUTHOR]

Polymer dielectrics with a high energy density, an outstanding breakdown strength, and a low dielectric loss are currently in great demand in the field of film capacitors. Here, on the basis of fundamental understanding of dielectric relaxation in cellulose, environmentally friendly regenerated cellulose-based dielectrics were fabricated by manipulating their intrinsic hydrogen bonding network, in which hydroxyl groups of cellulose were reacted with epichlorohydrin (ECH) to simultaneously reduce the density of the intra- and intermolecular hydrogen bonding networks and the crystallinity for activating the movement of polar groups. As a result, when the molar ratio of ECH to glucose units of cellulose is 1:1, the regenerated cellulose-based dielectrics exhibited the highest dielectric constant of 9.7 at 103 Hz with the dielectric loss in an order of 10−2 and an energy density of 2.16 J/cm3 with a high charge–discharge efficiency of >85% at 200 MV/m. This methodology presented here provides a promising avenue for designing and improving the dielectric properties of cellulose-based dielectrics. [ABSTRACT FROM AUTHOR]

Poly(propylene 2,5-furan dicarboxylate) (PPF) is an example of alipharomatic bio-based polyester which has a high potential for the replacement of its fossil-based terephthalate counterparts (PPT). PPF offers advantages over PPT owing to its brilliant properties. However, PPF often exhibits a slow rate of crystallization, which is a bottleneck for its successful synthesis. This has also caused limited research work on the use of PPF for the specific application. Therefore, in this study, PPF is melt compounded with microcrystalline cellulose (MCC) via twin-screw extrusion, which in turn enhances its crystallization. During its preparation, no toxic chemicals are used to modify the fibers or compatibilizers, indicating that the synthesis method follows green chemistry principles. The influence of the MCC on the thermal, structure and surface behaviors of PPF is analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry (DSC), thermo-gravimetric analysis and X-ray diffraction. The effect of the MCC on both non-isothermal and isothermal crystallization of PPF is also explored by using DSC. It is observed that crystallization is faster, while PPF is compounded with lower content of MCC. Similarly, the nucleating rate is intensified with the introduction of MCC. The incorporation of MCC significantly increased tensile modulus, strength and elongation of break of progressing PPF by 16%, 63% and 61%, respectively, at a content of 15 wt.% MCC. The blend also owned better oxygen and carbon dioxide barrier properties than neat PPF as a function of MCC content. This study is expected to spur further work on the synthesis of PPF composite for packaging applications. [ABSTRACT FROM AUTHOR]

The structure and properties of polymer film are greatly affected by the patterns on its surface arising from solution convection. Therefore, it is necessary to explore more detail mechanism of pattern formation. Herein, we have successfully designed variable patterns on the surface of cellulose films via roller coating method. The cellulose with three degrees of polymerization was used as raw material, and a solution of N,N-dimethyl-acetamide/lithium chloride (DMAc-LiCl) was selected as the solvent system. The pattern variations were controlled by the solution viscosity, which was affected by the degree of polymerization of cellulose, concentration and temperature of solution. The formation process of the pattern on cellulose film was in situ tracked by video recording with the help of carbon black tracker. It was found that the solution moved from the edge of the cell pattern to the center at a relatively lower viscosity (η < 8.06 Pa s), and finally formed a polygon pattern with the convex center. With the increasing of the solution viscosity (η ≥ 8.06 Pa s), the direction of its convection was completely opposite and a circular or circular-like combination pattern with concave center appeared on the surface of the cellulose film. The higher the viscosity, the larger the concave area. Moreover, the film with polygon pattern demonstrated excellent mechanical properties, and also exhibited a potential anti-counterfeiting value. These results could provide guidance in perfecting the theory of polymer fluid, and regulating the structure and properties of polymer products. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Five types of ZrO2 are used to simply establish an effective aqueous catalytic system with sulfuric acid for the hydrolysis of cellulose to sugar, respectively. By adjusting surface roughness and particle size of ZrO2, different adsorption is produced. Accordingly, following the thought to inhibit the self‐aggregation nature of cellulose, after the introduction of ZrO2 with adsorption in catalysts, the efficiency of the hydrolysis of cellulose to sugar is improved. The results show different ZrO2 can produce different effects during the hydrolysis of the cellulose with relatively low crystallinity. Under the optimal conditions, the conversion of cellulose and TRS yield reaches 95.5% and 93.6%, respectively. Through this research, it reveals the critical point to organize a feasible and useful way for the hydrolysis of cellulose to sugar with high efficiency in an aqueous system. An important theoretical and technical support is also provided for the conversion and utilization of cellulose in the future. [ABSTRACT FROM AUTHOR]

Utilization of modest to good strength and stiffness of polylactide (PLA) as well as overcoming its brittle phenomenon is the primary concern of this study. Therefore, melt-blending with a lab-scale two-screw extruder was conducted on PLA and micro-fibrillated cellulose (MFC) with and without epoxidized soybean oil (ESO) as a reactive plasticiser. Introducing ESO has a major effect on the blends' toughness. A low span scanning electron microscope (SEM) was used to observe PLAs transition from brittle to ductile behavior. PLA/MFC/ESO ternary blends' elongation-at-break, bending strain and notch impact strength were improved to 105, 9.7% and 7.20 kJ/m2 respectively. This assembly also helps in the increase of the plasticisation effect which leads to reduced glass transition Tg and crystallization Tc temperatures, observable using differential scanning calorimetry (DSC). Thermogravimetric analysis (TGA) shows an increase in ternary blends' decomposition temperature compared with neat PLA which suggests the blends are thermally stable. Fourier transform infrared (FTIR) spectroscopy allowed significant changes in peak positions to explain the interactions among blended components. The entire process rests on a simple, effective methodology whereby improved PLA/MFC blend toughness by ESO is achieved. [ABSTRACT FROM AUTHOR]

Cellulose-Ag@AgCl composite films were fabricated by one-step coagulation of the cellulose/1-Butyl-3-methylimidazolium chloride (BmimCl)solution with AgNO3. AgCl was firstly formed when AgNO3 was added into cellulose/BmimCl solution, and then the formed AgCl was further reacted with excess Cl−, leading to the complete dissolution of AgCl. The AgCl crystal would grow again from cellulose matrix in the air after the film formation. Meanwhile, AgCl could be partly decomposed into Ag° and formed Ag@AgCl under visible-light irradiation. The morphology of Ag@AgCl in cellulose matrix could be regulated by changing the molar ratio of BmimCl and AgNO3, the growth time of AgCl crystal and the concentration of cellulose solution. The cellulose composite film with stamen-like Ag@AgCl showed the best anti-fouling properties for methyl orange reagent under visible-light irradiation. This work also provided a simple pathway to regulate the morphology of Ag@AgCl in cellulose or other polymer matrices. [ABSTRACT FROM AUTHOR]

[Display omitted] • A nano-contacted binary complexes interface enhances photo-Fenton reaction notably; • The selective passing surface avoids the regeneration problems of nano-catalysts; • The delicate architecture on micro-reactor exhibits excellent recyclability. Fenton-based multi-component catalysts show great potential in water treatment due to the designable electron transfer structure, but balancing the requirements of recycling and degradation efficiency is still a formidable challenge. Herein, a novel core–shell structured cellulose-based microgel with solid titanium dioxide (TiO 2) shell and highly dispersed ferroferric oxide (Fe 3 O 4) in the core, were fabricated by Pickering emulsion and in-situ mineralization. The meticulously designed structure endowed microgel with selective passing surface that allowed the proton and oxidant to pass through, but selectively prevent the diffusion of contaminants to interior. And the enhanced photo-Fenton degradation via binary complexes interface between TiO 2 shell and highly dispersed Fe 3 O 4 exhibited removal rate of as high as 0.123 min−1 and 0.053 min−1 in decomposing methylene blue and tetracycline, respectively. Moreover, the degradation of contaminants occurred on the surface of microgel, markedly reducing the consumption of oxidant compared with the previous work of hydrogel immobilized catalyst. Due to the double protection provided by solid shell and hydrogel network, the as-prepared core–shell structured microgel maintained highly effective degradation after 5 rounds cyclic test. This study opens up a new avenue to develop highly efficient Fenton-based catalytic system with good recyclability, promoting its application in the wastewater treatment. [ABSTRACT FROM AUTHOR]

The native Cellulose-AgCl fiber have been firstly fabricated by one-step electrospinning of cellulose solution with poly(vinyl pyrrolidone) (PVP) and AgNO3. X-ray diffraction, Scanning electron microscopy (SEM), Energy dispersive spectrometer, Thermo-gravimetric analysis and Fourier transform infrared are used to characterize the crystal structure, morphology and composition of cellulose-AgCl nanocomposites. The results of SEM indicate that the size of AgCl in cellulose fiber matrix is able to be adjusted by the addition of Polyvinylpyrrolidone (PVP). The antimicrobial activity of the nanocomposites fiber is also tested against the model microbesE. coli(Gram-negative) andS. aureus(Gram-positive). The results indicate that cellulose-AgCl nanocomposites have a good antimicrobial activity, which is improving with the decrease of AgCl size in fiber matrix. This work provides a novel and simple way to adjust the AgCl size in electrospinning cellulose matrix which can be applied as functional biomaterials. [ABSTRACT FROM PUBLISHER]

[Display omitted] • In-situ cellulose mineralization in homogeneous system improves dispersion of TiO 2. • The excellent and pH-sensitive adsorption capacity of microsphere is obtained. • The microsphere exhibits an auto-accelerating degradation on Rhodamine B. • The intermediate-adsorbed microsphere obtains visible light responsive property. It is a daunting task to balance the catalyst stability and exposure of active site of highly efficient immobilizing photocatalyst system for wastewater treatment. In this study, an in-situ mineralization method based on homogeneous system was proposed to directly construct amorphous TiO 2 into cellulose hydrogel network as the crosslinker for efficiently and safely processing wastewater. This unique structure not only endowed TiO 2 /cellulose microsphere (TMS) with an adsorption capacity of 91.7 mg/g on methylene blue, which was approximately 14 times to cellulose microsphere containing commercial TiO 2 nanoparticles, but also made TMS reusable due to its pH sensitive adsorption capacity. More interestingly, TMS exhibited an auto-accelerating process in decomposing Rhodamine B where the degradation intermediate could act as the receptor of photo-regenerated holes to improve photocatalytical activity. In further cyclic test, the degradation rate constant of intermediate-adsorbed TMS was up to 0.02 mg−1min−1. Moreover, the intermediate-adsorbed TMS obtained visible light responsive property, including a removal ratio of 86.3 % against tetracycline (c 0 = 20 mg/L) in 120 min. This in-situ cellulose mineralization provides a new sight into the design of hydrogel immobilized catalyst system with high dispersion and active site exposure for efficient and safe water treatment. [ABSTRACT FROM AUTHOR]

Hydrogel supported photocatalyst, an efficient strategy for water remediation suffers from compromised catalytic activity and insufficient stability. Herein, a robust cellulose-based composite hydrogel with zinc oxide (ZnO)/silica (SiO 2) heterojunctions were fabricated by in-situ synthesis, where SiO 2 not only acted as a cross-linking agent to enhance the mechanical strength and stability of hydrogel, but also promoted the photocatalytic properties of ZnO via transferring the electron-hole pairs due to its surface state. As a result, a significant improvement in the mechanical properties of cellulose-based composite hydrogel was achieved, exhibiting a high compressive strength of 703.4 kPa. Moreover, the degradation efficiency of methylene blue (MB) under light irradiation by cellulose-based composite hydrogel was 95 % in 120 min and the removal ratio maintained as high as 90 % after eight degradation cycles. This study provides a low-cost and facile method to construct new hydrogel supports with high stability and efficient photocatalytic properties. [Display omitted] [ABSTRACT FROM AUTHOR]

By catalytically converting cellulose using a phosphate-modified hydroxyl-rich carbon-based catalyst (P@HRCBC), which was made by hydrothermal carbonization, glucose was successfully hydrolyzed from cellulose in an aqueous phase system (HTC). The glycosidic bond breaking catalyzed by the -PO 3 H 2 and the cellulose matrix lamellar exfoliation are both enhanced by the excellent adsorption capacity of the exceptionally rich –OH. The activity of cellulase is perfectly imitated. Within 120 min, the glucose output and the conversion of cellulose achieved 96.3% and 47.1%, respectively. The numerous ways that P@HRCBC adsorbs cellulose and cellobiose alter its catalytic ability and make separating glucose easier. After numerous cycles, the conversion of cellulose was maintained at 90.3%, thanks to the remarkable stability of –OH and -PO 3 H 2. P@HRCBC shows an actual "enzymatic" catalytic function that provides a new solution for the efficient green hydrolysis of cellulose into glucose. [Display omitted] • Hydrothermal reaction successfully used for the preparation of P@HRCBC. • The -PO 3 H 2 was successfully introduced into P@HEGCS. • Sugars are obtained from the catalytic hydrolysis of cellulose in a recyclable P@HEGCS system. • P@HRCBC exerts enzyme-like catalytic properties. [ABSTRACT FROM AUTHOR]

The fibrous structure of FS90@C/HPW12 enhances the contact area between catalyst and cellulose, thereby increasing effectiveness. The proximity of catalyst and cellulose leads to selective adsorption on the cellulose surface due to the numerous hydroxyl groups on the catalyst. Upon separation, the microstructure of the cellulose surface is impaired, resulting in the formation of linear scars. HWP easily hydrolyzes the detached fragments from the cellulose matrix into glucose, thereby enhancing the efficiency of catalytic conversion of cellulose into sugar. [Display omitted] • HPW-doped hydroxyl-rich hydrothermal carbon-coated fibrous silica catalyst. • Enhance the effective and selective hydrolysis of cellulose into sugars. • Created a stable local environment for cellulose hydrolysis. • The Cellulose surface is effectively disrupted, leading to rapid hydrolysis. Phosphotungstic acid hydrate (HPW)-doped hydroxyl-rich hydrothermal carbon-coated fibrous silica catalyst (FS@C/HPW) is fabricated to induce the highly efficient hydrolysis of cellulose to sugar in an ultra-low acid aqueous system. The obtained FS90@C/HPW12 owns good thermal stability under 200 °C and the highest specific surface area at 28 m2/g. Owing to its special fibrous microstructures, FS90@C/HPW12 can cause linear damage and structural fragmentation on the surface of cellulose during hydrolysis. Accordingly, rather highly efficient hydrolysis with the cellulose conversion of 100 %, total reducing sugar and glucose yields at 92.2 % and over 85 % is achieved in the aqueous system with FS90@C/HPW12 and 5 mmol/L H 2 SO 4. FS90@C/HPW12 also exhibits good reusability in multiple hydrolysis. This research provides a particular way for the design and synthesis of solid catalysts to induce the highly efficient hydrolysis of cellulose to sugar by chemical catalysis in a full aqueous system. [ABSTRACT FROM AUTHOR]

Carbon aerogels derived from biomass have been considered as potential microwave absorption (MA) materials because of the intrinsic hierarchical porous structure, low density, and excellent heat resistance. However, high carbonation temperature or long carbonation time is always required to achieve optimized MA performance. Herein, the low-temperature carbonization of carbon nanotube (CNT)/cellulose aerogel was realized to develop a carbon aerogel for efficient MA. Compared with the carbon aerogel derived from pristine cellulose, the incorporation of CNT endowed the CNT/cellulose-derived carbon aerogel with improved dielectric loss, and thus improved MA performance at reduced carbonation temperature. The carbon aerogel carbonized at only 550 °C for 2 h exhibited a minimum reflection loss value of −43.6 dB and a broad effective absorption bandwidth (reflection loss below −10 dB) of 7.42 GHz. The low carbonation temperature and outstanding MA performance make this new carbon aerogel be promising candidate for MA applications. [Display omitted] • With the aid of CNT, desirable dielectric loss of resultant carbon aerogel was achieved at reduced carbonation temperature and time without destroying the intrinsic hierarchical porous structure. • CNT was uniformly introduced into cellulose aerogel without damaging the structure. • The carbon aerogel exhibited a minimum reflection loss value of -43.6 dB and a broad effective absorption bandwidth (reflection loss below -10 dB) of 7.42 GHz. [ABSTRACT FROM AUTHOR]

Raspberry-like carbon layer coated silica nanoparticles (MSN-x-NH 2 @C) with controllable hydroxyl-rich rough surface is designed and synthesized by use of alkaline etching strategy and hydrothermal carbonization (HTC) method, which is utilized as catalyst to provide particular interaction with cellulose between the solid-solid interfaces. Through the control of surface roughness of the raspberry-like catalyst, it induces the formation of local area with strong absorption on the surface and thus enhance the capability to disrupt the aggregated structure of cellulose. Accordingly, in low acidic aqueous system with MSN-x-NH 2 @C, the cellulose conversion rate is up to 91.99% with the total reducing sugar yield at 81.46% and glucose yield of ∼70% after the second hydrolysis in aqueous system. Furthermore, the obtained MSN-x-NH 2 @C exhibits good thermal stability and reusability. This research provides a new perspective for the design and preparation of nano-sized solid catalyst with controlled surface topological structure to enable the surface adsorption capability towards cellulose more efficiently in aqueous system. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel dual-responsive cellulose-based fluorescent material was fabricated in a CO 2 switchable solvent, which could be used as smart probe for "turn off" for Fe3+ detection, "turn on" for freshness monitor, and "turn-on-turn-off" for information encryption. [Display omitted] • Cellulose was employed for the fabrication of dual-responsive fluorescent materials. • The CO 2 switchable solvent system was used for the highly effective dissolution and functionalization of cellulose. • The turn-off fluorescent responsive ability towards Fe3+ is due to the coordination of Fe3+ with the carbonate linkage. • The turn-on fluorescent responsive ability towards amine is due to the remove of the acetyl group by aminolysis reaction. • The combination of the dual-responsive property enables the application in the field of information encryption. Fabrication of multi-responsive fluorescent sensors for real-time and visual monitoring or detection is practical and challenging. Herein, a novel cellulose-based fluorescent functional material with dual-responsive properties arising from two different functional sites was successfully designed and prepared in a CO 2 switchable solvent. Cellulose was effectively dissolved in this solvent and easily functionalized by successively grafting poly (lactic acid) and 7-hydroxy-4-trifluoromethyl coumarin (HFC) onto the cellulose backbone, resulting in C- g -PLLA/HFC with good processibility and fluorescence quenching response (turn off) towards Fe3+ due to the coordination of Fe3+ with the carbonate linkage. Acetylation of HFC under microwave-assisted conditions gave rise to C- g -PLLA/HFC-Ac which showed fluorescence enhancement response (turn on) to various organic amines because of the removal of the acetyl group by aminolysis reaction. Therefore, they could be respectively used for selective identification and detection of Fe3+, and real-time, accurate and visual monitoring of aquatic product freshness. Furthermore, an interesting application for irreversible information encryption was demonstrated by combining the dual-responsive property. This study suggests a new strategy for constructing cellulose-based functional material with multiple responsiveness and applications. [ABSTRACT FROM AUTHOR]

Non-thermal effect of microwave is precisely revealed as an important factor to strengthen the hydrolysis of cellulose to sugar by a new method of synchronous cooling assisted microwave driving. Using this particular method, the thermal effect is mandatorily removed from the hydrolysis of cellulose. After systematic analysis of the hydrolysis of low crystalline regenerated cellulose (RC), the non-thermal effect of microwave is proved to strengthen hydrolysis. The enhancement of non-thermal effect effectively weaken the interaction between the hydroxyl groups of -O(2)H and -O(6)H, as well as strengthen interaction between the hydroxyl groups of -O(3)H and -O(5)H within one single molecular chain. It leads to the reduction of regularity of molecular chain and thus inhibits the recrystallization of RC. As a result, the efficiency of hydrolysis is greatly improved. This research provides an important theoretical support and technical guidance to construct new microwave driven hydrolysis with high efficiency in the future. [ABSTRACT FROM AUTHOR]

An anti-fouling and antibacterial surface of cellulose film was obtained by one-step coagulation of the cellulose-LiCl/Dimethyl acetamide (DMAc) solution with AgNO 3 and polyvinyl pyrrolidone (PVP). The AgCl nanocrystals were embedded on the surface of cellulose film with the assistance of PVP, and the Ag@AgCl was formed due to the partly decomposition of AgCl under the visible-light irradiation. Morphology and size of the Ag@AgCl in cellulose matrix could be regulated by changing the concentration of PVP. From a series of comparative tests, Ag@AgCl could be stably embedded on cellulose film at the concentration of 1 wt% PVP, and its photo-degradation efficiency could be still retained 89% after 5-cycle testing. Meanwhile, a dramatic reduction in viable bacteria was also observed within 120 min of exposure on this film, and when exposure time was 180 min, no active bacteria was observed.This work provided a simple pathway to construct the functional cellulose film which could be applied as packaging materials. [ABSTRACT FROM AUTHOR]