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As a renewable aromatic compound with enormous production potential, lignin has various potential high-value utilization pathways, but the success achieved in the field of photocatalysis is limited. Herein, this work prepares a new type of photocatalyst by modifying Graphitic Carbon Nitride Nanotubes (CNT) with self-assembled lignin nanospheres for the photocatalytic production of H 2 O 2 and the degradation of azo dyes. Under light conditions, lignin enhances the production of H 2 O 2 through oxygen reduction and collaborates with carbon nitride tubes to generate O 2 - and 1 O 2 . Furthermore, carbon nitride tubes form electron-rich regions with lignin, promoting the transfer of electrons from adsorbed aromatic pollutants to this region, thereby facilitating their degradation. The experimental results indicate that the addition of 5 % lignin significantly enhances the photocatalytic degradation efficiency of azo dyes, with a degradation rate 1.87 times higher than that of the original carbon nitride tubes. Furthermore, CNL also have excellent degradation ability to pollutants in actual wastewater. This study provides new insights and prospects for the high-value utilization of lignin, enabling it to be used as a photocatalytic co-catalyst to participate in the photocatalytic degradation of environmental pollutants., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Airborne particulate matter is a pressing environmental and public health concern globally. This study aimed to develop sustainable filtration materials from cellulose nanofibers (CNFs) modified with graphene oxide (GO) to capture fine particulates from air effectively. CNFs were extracted from α-cellulose via mechanical grinding and modified with 0.5-1.5 wt% GO solution by ultrasonication to produce CNF-GO nanocomposites. These were freeze-dried into highly porous, lightweight aerogels for air filtration applications. Fourier transform infrared spectroscopy (FT-IR) confirmed GO incorporation through hydroxyl group interactions. Field emission scanning electron microscopy (FE-SEM) revealed a porous 3D network with reduced porosity after GO addition due to pore blocking. X-ray diffraction analysis showed the cellulose I crystal structure was retained after modification. Brunauer-Emmett-Teller (BET) measurements indicated increased density but decreased surface area and pore volume with GO loading. The thermogravimetric analysis demonstrated improved thermal stability with GO incorporation due to oxidative reactions and a barrier effect. The particulate absorption efficiency markedly increased from 86.37 % to 99.98 % for CNFs modified with 1.5 wt% GO due to the high surface area, surface oxygen functionalities, and nanoplatelet morphology of GO. The nanofiber filters with 1.5 wt% GO exhibited a maximum absorption efficiency of 99.98 % and a quality factor of 0.0912 Pa -1 . Although GO reduced biodegradability, substantial degradation occurred under soil conditions. Overall, the sustainable, high-efficiency CNF-GO air filters developed in this work demonstrate immense promise for controlling air pollution and protecting human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This work aims to enhance the performance of the polyvinyl alcohol (PVA) composite by using cellulose nanocrystal (CNC) as reinforcement and copper nanoparticles (CuNPs)/reduced graphene oxide (rGO) as conducting and antimicrobial reagents. Firstly, rGO was loaded onto CuNPs using an eco-friendly microwave method. Different techniques characterized the components and prepared composites, which indicated the incorporation of cellulose nanocrystals and rGO@CuNPs within the polyvinyl alcohol matrix. Utilizing the clear zone of inhibition, the antibacterial test was quantified. Compared to the neat composite, the rGO@CuNPs loaded polyvinyl alcohol/ cellulose nanocrystal composites exhibited no bacterial growth against S. aureus, E. coli, and C. albicans. However, all composites did not have antifungal activity against A. niger. The combination of conductivity and interfacial polarization is the reason for the abrupt increase of permittivity with decreasing frequency. Besides, adding rGO@CuNPs improved the electrical conductivity. DC-Conductivity increased about a decade after adding cellulose nanocrystal to polyvinyl alcohol, then another decade after adding CuONPs. The electric loss modulus representation shows a systematic shift in the peak position towards higher frequencies, decreasing the so-called conductivity relaxation time. This is the main reason for the enhancement of conductivity. The systematic attenuation of peaks' height with increasing conductivity is still unclear., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Graphene oxide (GO), TiO 2 -NPs, HPMC, and shellac are environmentally green polymers and nanocomposites. This work aimed to create biodegradable composite films made of HPMC/shellac, HPMC/shellac-GO, and HPMC/shellac-GO/TiO 2 -NPs by film casting. TiO 2 -HPMC/shellac-GO matrix's dispersibility and mixing ability were characterized and observed using FTIR and XRD. XRD analysis shows that the crystallinity decreased within the composites due to breaking H-bonding. Compared to HPMC/shellac, TGA/DTG demonstrated the composite films' superior thermal stability. TiO 2 (0.08-0.16 %) was cast into a composite film comprising HPMC, shellac, and GO. The homogeneity of TiO 2 distribution in the composite film was shown using a SEM, which was also used to display the morphology of nanocomposite films. Nanocomposite films' thickness, air permeability, tensile strength, Young's modulus, and burst strength were examined. The results demonstrated that natural films prepared by a combination of shellac/GO with HPMC enhanced the fabricating of films' properties, the tensile strength increased by 231 % (from 16 to 53 MPa) in HPMC and HPSG2 (HPMC 1.9 g/shellac 0.25 g/GO 0.125 g in 100 mL) respectively, whereas the contact angle did not change. And after addition of TiO 2 -NPs, there were high enhancements in HPMC films' properties, such tensile strength increased by 212 % (from 16 to 50 MPa), burst strength increased by 20.96 % (3.1 to 3.75 Kg/cm 2 ), and the contact angle by 60.86 % (48 to 74°) in HPMC and HPSGT2 respectively. Compared to HPMC films, films exhibited the highest levels of antibacterial activity against E. coli, B. mycoides, and C. albicans. So, the composite films from HPMC/shellac/GO/TiO 2 -NPs are promising potential packaging materials., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In recent years, the pursuit of high-performance nano-flexible electronic composites has led researchers to focus on nanocellulose-graphene composites. Nanocellulose has garnered widespread interest due to its exceptional properties and unique structure, such as renewability, biodegradability, and biocompatibility. However, nanocellulose materials are deficient in electrical conductivity, which limits their applications in flexible electronics. On the other hand, graphene boasts remarkable properties, including a high specific surface area, robust mechanical strength, and high electrical conductivity, making it a promising carbon-based nanomaterial. Consequently, research efforts have intensified in exploring the preparation of graphene-nanocellulose flexible electronic composites. Although there have been studies on the application of nanocellulose and graphene, there is still a lack of comprehensive information on the application of nanocellulose/graphene in flexible electronic composites. This review examines the recent developments in nanocellulose/graphene flexible electronic composites and their applications. In this review, the preparation of nanocellulose/graphene flexible electronic composites from three aspects: composite films, aerogels, and hydrogels are first introduced. Next, the recent applications of nanocellulose/graphene flexible electronic composites were summarized including sensors, supercapacitors, and electromagnetic shielding. Finally, the challenges and future directions in this emerging field was discussed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Microcystins with leucine arginine (MC-LR) is a virulent hepatotoxin, which is commonly present in polluted water with its demethylated derivatives [Dha 7 ] MC-LR. This study reported a low-cost molecularly imprinted polymer network-based electrochemical sensor for detecting MC-LR. The sensor was based on a three-dimensional conductive network composed of multi-walled carbon nanotubes (MWCNTs), graphene quantum dots (GQDs), and gold nanoparticles (AuNPs). The molecularly imprinted polymer was engineered by quantum chemical computation utilizing p-aminothiophenol (p-ATP) and methacrylic acid (MAA) as dual functional monomers and L-arginine as a segment template. The electrochemical reaction mechanism of MC-LR on the sensor was studied for the first time, which is an irreversible electrochemical oxidation reaction involving an electron and two protons, and is controlled by a mixed adsorption-diffusion mechanism. The sensor exhibited a great detection response to MC-LR in the linear range of 0.08-2 μg/L, and the limit of detection (LOD) is 0.0027 μg/L (S/N = 3). In addition, the recoveries of the total amount of MC-LR and [Dha 7 ] MC-LR in the actual sample by the obtained sensor were in the range from 91.4 to 116.7%, which indicated its great potential for environmental detection.

In this study, we prepared spherical cellulose nanocrystals (S-CNCs) and stabilized n-hexadecane Pickering emulsions in conjunction with graphene oxide (GO), exploring the interaction between S-CNCs and GO in the emulsions. Both S-CNCs and GO are amphiphilic and synergistically stabilize Pickering emulsions by adhering to the surface of oil droplets and within the emulsion space through hydrogen bonding. GO's two-dimensional sheets assemble into a 3D network structure, further improving the stability of Pickering emulsions. Consequently, the stability of Pickering emulsions can be adjusted by altering the S-CNCs/GO ratio, modifying the spatial distribution relationship of stabilizers in the emulsions. At an S-CNCs concentration of 1 g/L and a GO concentration of 3 g/L, the Pickering emulsion demonstrated excellent stability and exhibited no delamination after 31 days of storage. Thus, the S-CNCs/GO combination serves as an effective Pickering emulsion stabilizer, utilizing the synergistic effect between the two components., Competing Interests: Declaration of competing interest The authors declare that there are no potential competing financial interests or personal relationships in the work, publication of this article., (Copyright © 2023. Published by Elsevier B.V.)

The diagnosis and treatment of many neurological and psychiatric problems depend on establishing simple, inexpensive, and comfortable electrochemical sensors for dopamine (DA) detection. Herein, 2,2,6,6 tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibers (TOC) were successfully loaded with silver nanoparticles (AgNPs) and/or graphite (Gr) and crosslinked by tannic acid, producing composites. This study describes a suitable casting procedure for the composite synthesis of TOC/AgNPs and/or Gr for the electrochemical detection of dopamine. Electrochemical impedance spectra (EIS), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) were employed to characterize the TOC/AgNPs/Gr composites. In addition, the direct electrochemistry of electrodes treated with the prepared composites was examined using cyclic voltammetry. The TOC/AgNPs/Gr composite-modified electrode improved electrochemical performance towards detecting dopamine compared to TOC/Gr-modified electrodes. Upon employing amperometric measurement, our electrochemical instrument has a wide linear range (0.005-250 μM), a low limit of detection (0.0005 μM) at S/N = 3, and a high sensitivity (0.963 μA μM -1  cm -2 ). Additionally, it was demonstrated that DA detection seemed to have outstanding anti-interference characteristics. The proposed electrochemical sensors meet the clinical criteria regarding reproducibility, selectivity, stability, and recovery. The straightforward electrochemical method utilized in this paper may provide a potential framework for creating dopamine quantification biosensors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Implementing parts per billion-level nitric oxide (NO) sensing at room temperature (RT) is still in extreme demand for monitoring inflammatory respiratory diseases. Herein, we have prepared a kind of core-shell structural Hemin-based nanospheres (Abbr.: Hemin-nanospheres, defined as HNSs) with the core of amorphous Hemin and the shell of acetone-derived carbonized polymer, whose core-shell structure was verified by XPS with argon-ion etching. Then, the HNS-assembled reduced graphene oxide composite (defined as HNS-rGO) was prepared for RT NO sensing. The acetone-derived carbonized polymer shell not only assists the formation of amorphous Hemin core by disrupting their crystallization to release more Fe-N 4 active sites, but provides protection to the core. Owing to the unique core-shell structure, the obtained HNS-rGO based sensor exhibited superior RT gas sensing properties toward NO, including a relatively higher response ( R a / R g = 5.8, 20 ppm), a lower practical limit of detection (100 ppb), relatively reliable repeatability (over 6 cycles), excellent selectivity, and much higher long-term stability (less than a 5% decrease over 120 days). The sensing mechanism has also been proposed based on charge transfer theory. The superior gas sensing properties of HNS-rGO are ascribed to the more Fe-N 4 active sites available under the amorphous state of the Hemin core and to the physical protection by the shell of acetone-derived carbonized polymer. This work presents a facile strategy of constructing a high-performance carbon-based core-shell nanostructure for gas sensing.

Despite significant advances in early detection and personalized treatment, cancer is still among the leading causes of death globally. One of the possible anticancer approaches that is presently receiving a lot of attention is the development of nanocarriers capable of specific and efficient delivery of anticancer drugs. Graphene-based materials are promising nanocarriers in this respect, due to their high drug loading capacity and biocompatibility. In this review, we present an overview on the interactions of graphene-based materials with normal mammalian cells at the molecular level as well as cellular and subcellular levels, including plasma membrane, cytoskeleton, and membrane-bound organelles such as lysosomes, mitochondria, nucleus, endoplasmic reticulum, and peroxisome. In parallel, we assemble the knowledge about the interactions of graphene-based materials with cancerous cells, that are considered as the potential applications of these materials for cancer therapy including metastasis treatment, targeted drug delivery, and differentiation to non-cancer stem cells. We highlight the influence of key parameters, such as the size and surface chemistry of graphene-based materials that govern the efficiency of internalization and biocompatibility of these particles in vitro and in vivo. Finally, this review aims to correlate the key parameters of graphene-based nanomaterials specially graphene oxide, such as size and surface modifications, to their interactions with the cancerous and non-cancerous cells for designing and engineering them for bio-applications and especially for therapeutic purposes., 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 The Authors. Published by Elsevier B.V. All rights reserved.)

Improving the gas molecule barrier performance and structural stability of bio-plastic films dramatically contribute to packaging and protective fields. Herein, we proposed a novel nanocomposite film consisting of cellulose acetate (CA)/polyethyleneimine (PEI)/reduced graphene oxide (rGO)-NiCoFeO x ) with high gas barrier property by applying "molecular glue" and "nano-patching" strategies. Systematical investigations demonstrated that the CA/rGO interfacial interaction was effectively enhanced due to the "molecular glue" role of PEI chains via physical/chemical bonds and the defective regions in rGO plane were nano-patched through hydrophilic interactions between edged oxygen-containing functional groups and ultrafine NiCoFeO x nanoparticles (~3 nm). As a result, the oxygen and moisture transmission rates of the prepared CA/PEI/rGO-NPs hybrid film were significantly reduced to 0.31 cm 3  ∗ μm/(m 2  ∗ d ∗ kPa) and 314.23 g/m 2  ∗ 24 h, respectively, which were 99.60% and 54.69% lower than pristine CA films. Meanwhile, the tensile strength of hybrid film was increased from 25.90 MPa to 40.67 MPa. More importantly, the designed nanocomposite film possesses excellent structural stability without obvious GO layer shedding and hydrophobicity attenuation after persistent bending at least 100 times. The exceptional robust and high gas barrier film displays great promising application in food, agriculture, pharmaceuticals and electronic instruments packaging industry., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Aim: This study aims to prepare a nanocomposite (HPMC/5-FL@GO) from hydroxypropyl methylcellulose (HPMC) and graphene oxide (GO) as biocompatible materials. The nanocomposite enhances the drug activity of immobilized 5-fluorouracil (5-FU), decreasing the side effect of long-run treatment protocols with highly efficient drug-drug activity., Method and Results: Different samples were characterized by ATR-FTIR spectroscopy, X-ray diffraction, scanning electron microscopy coupled with energy dispersive X-ray analysis, transmission electron microscopy, thermogravimetric analysis, and dynamic light scattering along with cytotoxicity and anticancer study. A homogenous and compatible nanocomposite structure with a homogenous drug distribution was confirmed. Furthermore, the prepared nanocomposite has a low cytotoxicity effect against normal Vero cell lines compared with 5-FU. The antitumor activities of the same nanocomposite (20.4 and 74.3 μg mL -1 on A549 and HepG-2) were lower than that of 5-FU (54.1 and 103 μg mL -1 on A549 and HepG-2)., Conclusion and Implications: According to the attained results, the HPMC/5-FL@GO can apply in a biomedical application such as cancer therapy with the unique biocompatible to human cells., (© 2021 Wiley-VCH GmbH.)

It is a great challenge to develop efficient room-temperature sensing materials and sensors for nitric oxide (NO) gas, which is a biomarker molecule used in the monitoring of inflammatory respiratory diseases. Herein, Hemin (Fe (III)-protoporphyrin IX) is introduced into the nitrogen-doped reduced graphene oxide (N-rGO) to obtain a novel sensing material HNG-ethanol. Detailed XPS spectra and DFT calculations confirm the formation of carbon-iron bonds in HNG-ethanol during synthesis process, which act as electron transport channels from graphene to Hemin. Owing to this unique chemical structure, HNG-ethanol exhibits superior gas sensing properties toward NO gas (R a /R g  = 3.05, 20 ppm) with a practical limit of detection (LOD) of 500 ppb and reliable repeatability (over 5 cycles). The HNG-ethanol sensor also possesses high selectivity against other exhaled gases, high humidity resistance, and stability (less than 3% decrease over 30 days). In addition, a deep understanding of the gas sensing mechanisms is proposed for the first time in this work, which is instructive to the community for fabricating sensing materials based on graphene-iron derivatives in the future., (© 2022 Wiley-VCH GmbH.)

In this work, biocompatible, antimicrobial, and antiviral nanocomposites were prepared through two steps. In the first step, periodate oxidation of cellulose was performed to get dialdehyde cellulose (DAC). The second step included the reaction of DAC with sulfur-containing amino acids included Cysteine (Cys) and Methionine (Meth) in the presence of graphene oxide (GO). The prepared nanocomposites were characterized via FT-IR, SEM, TEM, and TGA. Antimicrobial and antiviral activities for all designed nanocomposites besides DAC were carried out. Both DAC/GO/Cys and DAC/GO/Meth exhibited a promising antimicrobial activity against Gram-negative (E. coli and P. aeruginosa), Gram-positive (B. subtilis and S. aureus), and unicellular fungi (C. Albicans and C. neoformans), while the DAC/GO/Cys/Meth nanocomposite was the lowest. Moreover, all designed nanocomposites have a strong antiviral activity against Herpes simplex virus 1(HSV-1) at minimum nontoxic concentration. Additionally, Computational procedures and Molecular docking showed the reactivity and stability of the molecules that have biological activity against Gram-positive, Gram-negative, and HSV-1. As well as DAC incorporation with amino acid enhanced their reactivity and their interaction., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Gas sensors have aroused much attention in recent years for the important effect in modern society. Graphene, with unique structure and characteristic properties, has been considered as a promising candidate for fabricating high-performance gas sensor. Great efforts in current research are directed towards exploiting various graphene-based gas sensors, but the core of gas sensing study is how to enhance the gas sensing performance. Herein, we propose a perspective that focuses on the strategies for sensing performance enhancement of graphene-based gas sensors. Several strategies are reviewed such as the modification of graphene with organic molecules, functionalization by metal oxide or noble metals, and nanostructural engineering. Particular emphasis is also provided to clarify the mechanism for the gas sensing enhancement. Further, the sensor device design is also concerned for the significant effect on reaching full potential of the gas sensing materials and realizing multifunctional integration. Finally, the opportunities and challenges for the development of gas sensors are pointed out., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Biomass, as the most abundant and sustainable resource on the earth, has been regarded as an ideal carbon source to prepare various carbon materials. However, manufacturing shape-memory carbon aerogels with excellent compressibility and elasticity from biomass remains an open challenge. Herein, a cellulose-derived carbon aerogel with an anisotropic architecture is fabricated with the assistance of graphene oxide (GO) through a directional freeze-drying process and carbonization. The carbon aerogel displays excellent shape-memory performances, with high stress and height retentions of 93.6% and 95.5% after 1000 compression cycles, respectively. Moreover, the carbon aerogel can identify large ranges of compression strain (10-80%), and demonstrates excellent current stability during cyclic compression. The carbon aerogel can precisely capture a variety of biological signals in the human body, and thus can be used in wearable electronic devices.

In the present research work, 2D-Porous NiO decorated graphene nanocomposite was synthesized by hydrothermal method to monitored the concentration of epinephrine (EPI). The morphology (SEM and TEM) results confirmed 2D-Porous NiO nanoparticles firmly attached over graphene nanosheets. FTIR and XPS analysis confirmed the formation of nickel oxide formation and complete reduction of GO to rGO. The electrochemical activity of the proposed NiO-rGO/GCE modified electrode on epinephrine was analyzed by simple cyclic voltammetry technique. The proposed low cost NiO-rGO/GCE modified electrode showed excellent catalytic activity over GCE and rGO/GCE electrodes. Due to its high conductivity and charge transfer ability of the NiO-rGO/GCE modified electrode exhibited high sensitivity of EPI at optimized conditions. The anodic peak current of the EPI linearly increases with increasing the concertation of EPI. A wide linear range (50 μM-1000 μM) was achieved with high correlation coefficient (R 2  = 0.9986) and the limit of detection (LOD) of NiO-rGO/GCE modified electrode was calculated to be 10 μM. NiO-rGO/GCE electrode showed good stability and repeatability towards the EPI oxidation. Mainly, the proposed NiO-rGO/GCE modified electrode showed good sensitivity of EPI in the human biological fluid with high recovery percentage. The low cost, NiO-rGO/GCE electrode could be the promising sensor electrode for the detection of Epinephrine in the real samples., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Renewable lignocellulosic biomass can be effectively transformed to value-added products, enabling fast growth of related downstream processing. However, valorization of the by-produced cellulose-poor fraction, which is also in large volumes, is only occasionally reported regarding existing technologies. Here, a simple, general, and effective strategy for fabricating graphene quantum dots (GQDs) from the Miscanthus (MC) biorefinery waste consisting of sugars and depolymerized lignin, is developed. This process involves the fast and selective removal of most lignin and hemicellulose based on mild acid hydrotrope fractionation, with followed hydrothermal carbonization. The as-fabricated MC-derived GQDs (M-GQDs) exhibit several advantages such as few-layer graphene-like single crystalline structure, sulfur and nitrogen co-doping, bright fluorescence, excitation-dependent photoluminescence, and long fluorescence lifetime (11.95 ns). Furthermore, M-GQDs present prominent fluorescence reduction in the presence of Fe 3+ with good linearity (≤0.995) and very low detection limit (≥1.41 nM). Later, it is found that the observed high sensitivity for Fe 3+ is based on a dynamic quenching mechanism, which is caused by the Fe 3+ -induced increase in both the energy dissipation and photogenerated electron consumption. This work is anticipated to open new opportunities for promoting the integral valorization of biomass and sensitive fluorometric detection of Fe 3+ ., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Bacterial breeding is the main cause of food perishability, which is harmful to human health. Silver nanoparticles (AgNPs) are one of the most widely used antimicrobial agents, but they are easy to release and cause cumulative toxicity. In this work, with corn stalk as green reductant and GO as template, a simple electrostatic self-assembled sandwich-like chitosan (CS) wrapped rGO@AgNPs nanocomposite film (CS/rGO@AgNPs) was synthesized to achieve stabilizing and controlled-release of AgNPs. The results showed that the the CS/rGO@AgNPs film continued releasing AgNPs for up to 14 days, and the final release amount of silver nanoparticles was only about 1.9 %. More importantly, the nanocomposite film showed durable antibacterial effect and good antibacterial activity against E. coli and S. aureus, and they showed no toxicity to cells. Hence, the nanocomposite film has potential application as an effective and safe packaging material to prolong the shelf life of food products., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The current work focuses on a cheap and simple preparation of highly conducting chitosan/hydroxyl ethylcellulose/polyaniline loaded with graphene oxide doped by silver nanoparticles (CS/HEC/PAni/GO@Ag) bionanocomposite as a biodegradable and biocompatible hydrogel for energy storage technology. Scanning electron microscopy (SEM) displays the compatibility of chitosan, hydroxyl ethyl cellulose, and polyaniline and a good distribution of GO@Ag-NPs in bionanocomposite hydrogels. X-ray diffraction (XRD) displayed the structure and existence of GO@Ag-NPs in the matrix. The swelling percentage and the antibacterial activities slightly increased with raising the content of GO@Ag-NPs. Also, the presence of both chitosan and cellulose improves the biodegradation of the fabricated bionanocomposites, which is increased by adding GO. Moreover, the incorporation of 5% GO@Ag-NPs in hydrogels enhances dc-conductivity by about 25 times from 3.37 × 10 -3 to 8.53 × 10 -2 S/cm. The fabricated hydrogels are inexpensive, eco-friendly, and have high capacitance and permittivity, and so they can store electrical energy., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest to be disclosed in this work., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The development of intelligent and multifunctional hydrogels having photothermal properties, good mechanical properties, sustained drug release abilities with low burst release, antibacterial properties, and biocompatibility is highly desirable in the biomaterial field. Herein, mesoporous polydopamine (MPDA) nanoparticles wrapped with graphene oxide (GO) were physically cross-linked in cellulose nanofibril (CNF) hydrogel to obtain a novel MPDA@GO/CNF composite hydrogel for controllable drug release. MPDA nanoparticles exhibited a high drug loading ratio (up to 35 wt %) for tetracycline hydrochloride (TH). GO was used to encapsulate MPDA nanoparticles for extending the drug release time and reinforcing the physical strength of the obtained hydrogel. The mechanical strength of the as-fabricated MPDA@GO/CNF composite hydrogel was five times greater compared to that of the pure CNF hydrogel. Drug release experiments demonstrated that burst release behavior was significantly reduced by adding MPDA@GO. The drug release time of the MPDA@GO/CNF composite hydrogel was 3 times and 7.2 times longer than that of the polydopamine/CNF hydrogel and pure CNF hydrogel, respectively. The sustained and controlled drug release behaviors of the composite hydrogel were highly dependent on the proportion of MPDA and GO. Moreover, the rate of drug release could be accelerated by near-infrared (NIR) light irradiation and pH value change. The drug release kinetics of the as-prepared composite hydrogel was well described by the Korsmeyer-Peppas model, and the drug release mechanism of TH from the composite hydrogel was anomalous transport. Importantly, this carefully designed MPDA@GO/CNF composite hydrogel showed good biocompatibility through an in vitro cytotoxicity test. In particular, the toxicity of GO was well shielded by the CNF hydrogel. Therefore, this novel MPDA@GO/CNF composite hydrogel with an encapsulation structure for controllable drug release and toxicity shielding of GO could be used as a very promising controlled drug delivery carrier, which may have potential applications for chemical and physical therapies.

In this paper, a novel way for high value-added application of lignosulfonate is presented. In this study, we use lignosulfonate nanosheets to fabricate a free-standing, binder-free, ultrathin and light-weight conductive film electrode via vacuum filtration method. The results show that LS is a promising candidate material for the preparation of electrochemical capacitor film electrode. It is worth mentioning that we use non-toxic, pollution-free aqueous solution (water) over organic solvents as the dispersion during the reductive graphene oxide (RGO) preparation process. The electrochemical measurements exhibit that the resistivity of lignosulfonate nanosheets/RGO (LNRGO) film electrode is 0.66 × 10 -3 kΩ cm -1 . The specific capacitance of the LNRGO film electrode is calculated to be 120 mF cm -2 at the current density of 0.2 mA cm -2 , which is approximately 6.67 times larger than that of RGO-water film electrode., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2020. Published by Elsevier B.V.)

NCF/GO hybrid nanofillers with excellent UV-shielding properties were prepared by using TEMPO-oxidized nanocellulose fibrils (NCF) and graphene oxide (GO) as raw materials; different mass ratios of NCF to GO (2: 1, 4: 1, 8: 1, and 16: 1) were used. The NCF and GO were then combined and used as a hybrid filler to study the synergistic effects on polyvinyl alcohol (PVA) nanocomposites. With 5% hybrid nanofiller, the UV-shielding performance of the PVA/NCF/GO composite film was higher than 90%. The tensile strength and Young's modulus of the PVA/CG-2 composite film increased by 74.5% and 278.0%, respectively, and the water absorption decreased by 59%. Moreover, the thermal stabilities of the nanocomposites also improved. This synergistic effect improved the performance of the hybrid nanofiller by avoiding the agglomeration of nanofillers in the polymer matrix and improving the homogeneity of the dispersion. The synergistic effect between the fillers provides a new idea for the preparation of novel multifunctional nanocomposites., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this work, reduced graphene oxide/metal organic framework composites (RGO/MOF) have been fabricated for the purpose of activating persulfate (PS) successfully first time. Benefiting from the abundant active sites of composites and the excellent electron conductivity arising from repaired large π conjugate plane structure, RGO/MIL-101(Fe) performed better than RGO and MIL-101(Fe) for PS activation and organic compounds degradation from aqueous. The physical-chemical properties of composite catalysts were fully characterized and the applications to the catalytic degradation of trichlorophenol (TCP) were evaluated. The results showed that RGO/MIL-101(Fe) could effectively degrade TCP, under the reaction conditions of pH 3.0, 20 mg/L TCP, 20 mM PS, 0.5 g/L catalyst, and the removal efficiency is 92% in 180 min. Furthermore, chemical reduction and thermal process played key role in regulating defect levels and electron transfer channels. The obtained adsorptive and conductive graphene allow rapid electron transport between free radicals and enriched contaminants. These advancements of the structure and chemical properties were beneficial to improve the catalytic activity in the activation of PS. Finally, a possible activation mechanism was also investigated, which involved the prevailing free radical pathway and recessive non-radical pathway., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Due to the rapid development of industrialization, the water resources on which we depend are facing unprecedented challenges. Dyes, as an indispensable substance in our lives, have caused great pollution to the water resources in nature, and the removal of dyes from wastewater is becoming an important topic. A porous xylan/poly(acrylic acid)/graphite oxide nanocomposite was prepared by graft polymerization and used for adsorption of cationic ethyl violet dye in wastewaters in this paper. Various techniques, i.e., Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, elemental analysis, scanning electron microscopy, and ultraviolet-visible spectroscopy, were used to study this composite. Adsorption isotherm measurements showed that the composite's adsorption behavior fits the Langmuir isotherm adsorption model. Adsorption tests showed that this material has excellent adsorption properties; the maximum adsorption capacity for ethyl violet dye was 273.99 mg/g. Investigation of the adsorption mechanism indicated that electrostatic forces and π-π effects are mainly involved in adsorption. Desorption cycling tests showed that the adsorption efficiency of the composite was still over 95% after 3 cycles. These results show that this porous xylan/poly (acrylic acid)/graphite oxide nanocomposite has potential applications in cationic dye removal., (Copyright © 2019 Elsevier B.V. All rights reserved.)

As a kind of potential absorbent, polysaccharide materials are limited due to weak stability, low absorption and recovery rate. Herein, a novel composite adsorbent - the magnetic composite gel beads (CMC/SA/graphene oxide@Fe 3 O 4 ) were prepared by combining carboxymethyl chitosan (CMC), sodium alginate (SA) with graphene oxide@Fe 3 O 4 , and then utilized for the adsorption of Cu 2+ , Cd 2+ and Pb 2+ from the wastewater. The physicochemical property of CMC/SA/graphene oxide@Fe 3 O 4 beads were characterized in detail. The CMC/SA/graphene oxide@Fe 3 O 4 magnetic gel beads could separate easily from the wastewater and showed a higher stability due to the addition of graphene oxide@Fe 3 O 4 . The adsorption experiments show that the adsorption of Cu 2+ , Cd 2+ and Pb 2+ on the magnetic gel bead was well fitted with pseudo-second-order model and Langmuir isotherm model, and the maximum adsorption capacity of Cu 2+ , Cd 2+ and Pb 2+ reached 55.96, 86.28 and 189.04 mg/g, respectively. Moreover, the magnetic gel beads had selective adsorption toward Pb 2+ . In addition, the magnetic gel beads still obtained 90% of the adsorption rates after five cycles, and showed good adsorption efficiency in the simulated real environment. This work proves that the CMC/SA/graphene oxide@Fe 3 O 4 magnetic gel beads as the adsorbents have promising potential in wastewater treatment., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A functionalized paper based on gold nanoparticles (Au NPs) conjugated graphene oxide (GO) was developed for near-infrared (NIR) laser triggered photothermal ablation against infectious bacterial pathogens. Firstly, quaternized carboxymethyl chitosan (QCMC) not only acted as reducing agent to synthesize Au NPs, but also functioned as coupling agent to link up Au NPs with GO. Au-QCMC-GO(+) was supposed to synergistically intensify the photothermal effect, which was then mixed with nanocellulose to form a functionalized paper via vacuum filtration. The photothermal efficiency, antibacterial treatment and mechanical property of Au-QCMC-GO(+)/nanocellulose paper were investigated. Excited by NIR laser irradiation, Au-QCMC-GO(+)/nanocellulose paper generated a temperature rise over 80 °C, sufficient for photothermal ablation upon both Gram-positive bacteria (Bacillus subtilis and Stapylococcus aureus) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Additionally, Au-QCMC-GO(+)/nanocellulose paper showed a remarkable enhancement in tensile strength, bursting index and tear index compared to those of pure nanocellulose paper., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Endowing materials with chirality and exploring the responses of the material under circularly polarized light (CPL) can enable further insight into the physical and chemical properties of the semiconductors to be gained, thus expanding on optoelectronic applications. Herein a bioinspired mesoporous chiral nematic graphitic carbon nitride (g-C 3 N 4 ) for efficient hydrogen evolution with polarized light modulation based on chiral nematic cellulose nanocrystal films prepared through silica templating is described. The mesoporous nematic chiral g-C 3 N 4 exhibits an ultrahigh hydrogen evolution rate of 219.9 μmol h -1 (for 20 mg catalyst), corresponding to a high enhancement factor of 55 when compared to the bulk g-C 3 N 4 under λ>420 nm irradiation. Furthermore, the chiral g-C 3 N 4 material exhibits unique photocatalytic activity modulated by CPL within the absorption region. This CPL-assisted photocatalytic regulation strategy holds great promise for a wide range of applications including optical devices, asymmetric photocatalysis, and chiral recognition/separation., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This work reported chitosan derivatives (CSD)/reduced graphene oxide (rGO) blending with alginate to prepare hydrogel beads for small-molecule drug delivery for the first time. At the beginning, graphene oxide (GO) was successfully reduced using diverse CSD as reducing and stabilizing agents via facile heating. Then the obtained CSD/rGO was blended with alginate and crosslinked into hydrogel beads in CaCl2 solution. Finally, the beads were systematically evaluated as novel vehicles for pH-responsive small-molecule drug delivery. The optimal CSD/rGO/alginate beads showed a high drug-loading efficiency of 82.8% on small-molecule fluorescein sodium (FL), outstanding sustainable release of 71.6% upon 150h at a physiological pH and quick-release of 82.4% drug content at 20h in an acidic medium. Additionally, the cytotoxicity assay result suggested that the CSD/rGO/alginate beads showed negligible cytotoxicity to hepatic stellate cell lines, opening up possibilities for safe and efficient drug delivery., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Ethylenediaminetetraacetic acid (EDTA) forms stable complexes with toxic metals such as nickel due to its strong chelation. The electro-Fenton (EF) process using a cathode made from palladium (Pd), reduced graphene oxide (RGO) and carbon felt, fed with air, exhibited high activities and stability for the removal of 10 mg L(-1) EDTA-Ni solution. Pd/RGO catalyst was prepared by one-pot synthesis; the scanning electron microscopy and X-ray diffraction analysis indicated nanoparticles and RGO were well distributed on carbon felt, forming three dimensional architecture with both large macropores and a mesoporous structure. The cyclic voltammetric results showed that the presence of RGO in Pd/RGO/carbon felt significantly increased the current response of two-electron reduction of O2 (0.45 V). The key factors influencing the removal efficiency of EDTA-Ni, such as pH, current and Fe(2+) concentration, were investigated. Under the optimum conditions, the removal efficiency of EDTA-Ni reached 83.8% after 100 min EF treatment. Mechanism analysis indicated that the introduction of RGO in Pd/RGO/carbon felt significantly enhanced the electrocatalytic activities by inducing •OH in the EF process; direct H2O2 oxidation still accounted for a large amount of EDTA-Ni removal efficiency.