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Antibiotic resistance and the rise of untreatable bacterial infections pose severe threats to human health. Silver nanoparticles (AgNPs) have emerged as a promising antibacterial solution due to their broad-spectrum effectiveness. However, their relatively high cytotoxicity has limited their widespread application. In this study, ferulic acid (FA) was used as a reducing agent, while silver oxide served as a silver precursor to rapidly prepare FA-derived lignin (FAL) coated AgNPs (AgNPs@FAL) with a size ranging from 34.8 to 77.1 nm. Density functional theory (DFT) calculations indicated that the coating of FAL endowed AgNPs@FAL with high stability, preventing the oxidation of AgNPs prior to antibacterial applications. Cell experiments further indicated that AgNPs@FAL exhibited lower cell toxicity (â¼80 % viability of normal kidney cells cultured at 25 µg/mL AgNPs@FAL) compared to fully exposed commercially available citrate-modified AgNPs (AgNPs@CA). Antibacterial experiments revealed that the minimum inhibitory concentrations (MIC) of AgNPs@FAL against E. coli and S. aureus were 12.5 µg/mL and 25 µg/mL, respectively, surpassing the antibacterial effect of AgNPs@CA, as well as ampicillin and penicillin. Additionally, AgNPs@FAL was capable of disrupting E. coli and S. aureus biofilm formation. This novel AgNPs@FAL formulation presents a promising antibacterial solution, addressing limitations observed in conventional drugs.
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As a natural "binder," lignin fixes cellulose in plants to foster growth and longevity. However, isolated lignin has a poor binding ability, which limits its biomedical applications. In this study, inspired by mussel adhesive proteins, acidic/basic amino acids (AAs) are introduced in alkali lignin (AL) to form ionic-π/spatial correlation interactions, followed by demethylation to create catechol residues for enhanced adhesion activity. Atomic force microscopy reveals that catechol residues are the primary adhesion structures, with basic AAs exhibiting superior synergistic effects compared to acidic AAs. Demethylated lysine-grafted AL exhibits the strongest adhesion force toward skin tissue. Molecular dynamic simulation and density functional theory calculations indicate that adhesion against skin tissue mainly results from hydrogen bonds and cation-π interactions, with the adhesion mechanism being based on the Gibbs free energy of the Schiff base reaction. In summary, a biomimetic electrode based on lignin inspired by mussel adhesive proteins is prepared; the presented method offers a straightforward strategy for the development of biomimetic adhesives. Furthermore, this mussel-inspired adhesive can be used as a wearable bioelectrode in biomedical applications.
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Strong and transparent nanocellulose/montmorillonite (MMT) nanocomposite films with high filler content (≥50 wt %) are emerging as versatile materials for advanced applications due to their excellent optical, barrier, mechanical, and thermal properties, and environmental friendliness. Nonetheless, these films undergo a notable decline in optical and mechanical properties at high MMT loadings. This study first demonstrates that calcium-ion-induced tactoids are the key factor causing disordered structures in nanocomposite films, leading to the degradation of optical and mechanical properties. We then address this issue by employing a Ca2+ removal strategyâdialysis. Through removing 43% of free Ca2+, simultaneous improvements in both properties are observed. For example, in a nanocomposite film with 70 wt % MMT, light transmittance increases from 75.9 to 91.6%, and the tensile strength rises from 100.4 to 139.4 MPa. This work offers insights into developing strong and transparent nanocomposite films with high MMT contents.
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Despite the widespread utilization of nano silver composites in the domain of catalytic hydrogenation of aromatic pollutants in wastewater, certain challenges persist, including the excessive consumption of chemical reagents during the preparation process and the difficulty in recycling. In this study, silver ions were reduced in-situ by taking advantage of the adsorptive and reducing capacities of hydroxyls and amino groups on lignin porous microspheres (LPMs) under mild ultrasonic conditions, and lignin porous microspheres loaded with silver nanoparticles (Ag@LPMs) were conveniently prepared. Ag@LPMs had excellent catalytic and cycling performances for p-nitrophenol (4-NP), methylene blue (MB) and methyl orange (MO). The 4-NP could be completely reduced to 4-AP within 155 s under the catalysis of Ag@LPMs, with a pseudo-first-order kinetic constant of 1.28 min-1. Furthermore, Ag@LPMs could still complete the catalytic reduction of 4-NP within 10 min after five cycles. Ag@LPMs with the particle size ranging from 100 to 200 µm conferred ease of recycling, and the porous structure effectively resolved the issue of sluggish mass transfer encountered during the catalytic process. At the same time, the binding force of nano silver and LPMs obtained by ultrasonic was stronger than that of heating, so the materials prepared by ultrasonic had better cycling performance. Silver ions concentration and pH value in the preparation process affected the catalytic performance of Ag@LPMs, 50 mmol/L Ag+ and pH value of 7 turned out to be the optimization conditions.
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Lignina , Nanopartículas Metálicas , Microesferas , Prata , Lignina/química , Prata/química , Catálise , Porosidade , Nanopartículas Metálicas/química , Nitrofenóis/química , Oxirredução , CinéticaRESUMO
The bismuth anode has garnered significant attention due to its high theoretical Na-storage capacity (386 mAh g-1). There have been numerous research reports on the stable solid electrolyte interphase (SEI) facilitated by electrolytes utilizing ether solvents. In this contribution, cyclic tetrahydrofuran (THF) and 2-methyltetrahydrofuran (MeTHF) ethers are employed as solvents to investigate the sodium-ion storage properties of bismuth anodes. A series of detailed characterizations are utilized to analyze the impact of electrolyte solvation structure and SEI chemical composition on the kinetics of sodium-ion storage. The findings reveal that bismuth anodes in both THF and MeTHF-based electrolytes exhibit exceptional rate performance at low current densities, but in THF-based electrolytes, the reversible capacity is higher at high current densities (316.7 mAh g-1 in THF compared to 9.7 mAh g-1 in MeTHF at 50 A g-1). This stark difference is attributed to the formation of an inorganic-rich, thin, and uniform SEI derived from THF-based electrolyte. Although the SEI derived from MeTHF-based electrolyte also consists predominantly of inorganic components, it is thicker and contains more organic species compared to the THF-derived SEI, impeding charge transfer and ion diffusion. This study offers valuable insights into the utilization of cyclic ether electrolytes for Na-ion batteries.
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Transparent paper manufactured from wood fibers is emerging as a promising, cost-effective, and carbon-neutral alternatives to plastics. However, fully exploring their mechanical properties is one of the most pressing challenges. In this work, a strong yet tough transparent paper with superior folding endurance is prepared by rationally altering the native fiber structure. Microwave-assisted choline chloride/lactic acid deep eutectic solvent (DES) pulping is first utilized to isolate wood fibers from spruce wood. During this process, the S1 layer within the fibers is partially disrupted, forming protruding microfibrils that play a crucial role in enhancing cellulose accessibility. Subsequently, carboxymethylation treatment is applied to yield uniformly swollen carboxymethylated wood fibers (CM fibers), which improves the interaction between CM fibers during papermaking. The as-prepared transparent paper not only shows a 90% light transmittance (550 nm) but also exhibits impressive mechanical properties, including a folding endurance of over 26 000, a tensile strength of 248.4 MPa, and a toughness of 15.6 MJ m-3. This work provides a promising route for manufacturing transparent paper with superior mechanical properties from wood fibers and can extend their use in areas normally dominated by high-performance nonrenewable plastics.
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Solar-driven interfacial evaporation is recognized as a sustainable and effective strategy for desalination to mitigate the freshwater scarcity issue. Nevertheless, the challenges of oil contamination, salt accumulation, and poor long-term stability of the solar desalination process limit its applications. Herein, a 3D biomass-based multifunctional solar aerogel evaporator is developed for water production with fabricated chitosan/lignin (CSL) aerogel as the skeleton, encapsulated with carbonized lignin (CL) particles and Ti3C2TiX (MXene) nanosheets as light-absorbing materials. Benefitting from its super-hydrophilic wettability, interconnected macropore structure, and high broadband light absorption (ca. 95.50%), the prepared CSL-C@MXene-20 mg evaporator exhibited a high and stable water evaporation flux of 2.351 kg m-2 h-1 with an energy conversion efficiency of 88.22% under 1 Sun (1 kW m-2) illumination. The CSL-C@MXene-20 mg evaporator performed excellent salt tolerance and long-term solar vapor generation in a 3.5 wt.% NaCl solution. Also, its super-hydrophilicity and oleophobicity resulted in superior salt resistance and anti-fouling performance in high salinity brine (20 wt.% NaCl) and oily wastewater. This work offers new insight into the manufacture of porous and eco-friendly biomass-based photothermal aerogels for advanced solar-powered seawater desalination and wastewater purification.
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The characteristics of multi-hydroxyl structure and strong hydrogen bonding in polyvinyl alcohol (PVA) make its melting point close to its decomposition temperature, causing melt-processing difficulty. In this work, following the plasticization of small-molecule primary plasticizer acetamide, lignin was demonstrated as a green secondary plasticizer in realizing the melt processing and simultaneous reinforcement of PVA. During the plasticization process, lignin was able to combine with the hydroxyl groups of PVA, so as to destroy the hydrogen bonds and regularity of the PVA chains. The synergistic plasticization effect of lignin dramatically reduced the melting point of PVA from 185 °C to 151 °C. The thermal processing window of PVA composites was expanded from 50 °C to roughly 80 °C after introducing lignin. In contrast to acetamide, the addition of lignin significantly increased the tensile strength and Young's modulus of the composites to 71 MPa and 1.34 GPa, respectively. Meanwhile, lignin helped to hinder the migration of acetamide via hydrogen bonds. With the addition of lignin, the composites also displayed enhanced hydrophobicity and excellent UV shielding performance. The strategy of synergistic plasticization of lignin provides a feasible basis for the practical application of lignin in melt-processable PVA materials with good comprehensive properties.
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Lignina , Plastificantes , Álcool de Polivinil , Resistência à Tração , Lignina/química , Álcool de Polivinil/química , Plastificantes/química , Ligação de Hidrogênio , Temperatura , Módulo de Elasticidade , Interações Hidrofóbicas e HidrofílicasRESUMO
Constructing heteroatom-doped porous carbons with distinct charge storage properties is significant for high-energy-density supercapacitors, yet it remains a formidable challenge. Herein, we employed a thiocyanogen-modulated alkali activation strategy to synthesize N and S co-doped lignin hierarchical porous carbon (NSLHPC). In this process, thiocyanogen serves as a surface modulation mediator to substitute oxygen with nitrogen and sulfur species, while the combination of KOH activation and MgO template generates numerous nanopores within the carbon structure. The three-dimensional interconnected nanosheet architecture facilitates rapid ion transfer and enhances accessibility to active sites. Density functional theory (DFT) calculations demonstrate that introducing N and S heteroatoms through oxygen substitution reduces the adsorption energy barrier of Zn2+. Consequently, the optimized NSLHPC exhibits a remarkable specific capacitance of 438F/g at 0.5 A/g in 6 M KOH, delivering an energy density of 10.4 Wh/kg in the symmetric supercapacitor and an impressive energy density of 104.9 Wh/kg in the zinc-ion hybrid capacitor. The NSLHPC cathode also shows an excellent lifespan with capacitance retention of 99.0 % and Columbic efficiency of 100 % over 10,000 cycles. This study presents innovative strategies for engineering high-performance porous carbon electrode materials by emphasizing pore structure modulation and N, S co-doping as crucial approaches.
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Potassium-ion hybrid capacitors (PIHCs) represent a burgeoning class of electrochemical energy storage devices characterized by their remarkable energy and power densities. Utilizing amorphous carbon derived from sustainable biomass presents an economical and environmentally friendly option for anode material in high-rate potassium-ion storage applications. Nevertheless, the potassium-ion storage capacity of most biomass-derived carbon materials remains modest. Addressing this challenge, nitrogen doping engineering and the design of distinctive nanostructures emerge as effective strategies for enhancing the electrochemical performance of amorphous carbon anodes. Developing highly nitrogen-doped nanocarbon materials is a challenging task because most lignocellulosic biomasses lack nitrogen functional groups. In this work, we propose a general strategy for directly carbonizing supermolecule-mediated lignin organic molecular aggregate (OMA) to prepare highly nitrogen-doped biomass-derived nanocarbon. We obtained lignin-derived, highly nitrogen-doped turbine-like carbon (LNTC). Featuring a three-dimensional turbine-like structure composed of amorphous, thin carbon nanosheets, LNTC demonstrated a capacity of 377 mAh g-1 when used as the anode for PIHCs. This work also provides a new synthesis method for preparing highly nitrogen-doped nanocarbon materials derived from biomass.
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This study employs a combined computational and experimental approach to elucidate the mechanisms governing the interaction between lignin and urea, impacting lignin dissolution and subsequent aggregation behavior. Molecular dynamics (MD) simulations reveal how the urea concentration and temperature influence lignin conformation and interactions. Higher urea concentrations and temperatures promote lignin dispersion by disrupting intramolecular interactions and enhancing solvation. Density functional theory (DFT) calculations quantitatively assess the interaction energy between lignin and urea, supporting the findings from MD simulations. Anti-solvent precipitation demonstrates that increasing the urea concentration hinders the self-assembly of lignin nanoclusters. The findings provide valuable insights for optimizing lignin biorefinery processes by tailoring the urea concentration and temperature for efficient extraction and dispersion. Understanding the influence of urea on lignin behavior opens up avenues for designing novel lignin-based materials with tailored properties. This study highlights the potential for the synergetic application of MD simulations and DFT calculations to unravel complex material interactions at the atomic level.
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Lignin-based silver nanoparticles have been considered a promising antimicrobial material. However, it remains challenging to prepare ultra-small size silver nanoparticles sustainably with superior antibacterial performance. In this work, we modified ethanol-extracted lignin (EL) with carboxymethyl groups and further synthesized ultra-small particle size (3.8 ± 0.1 nm) nanosilver incorporated carboxymethyl lignin complexes (AgNPs@CEL) using ultrasonic technology. Due to the outstanding antibacterial properties of the ultra-small size nanosilver, AgNPs@CEL could cause 5.3 and 5.4 log10 CFU/mL reduction against E. coli and S. aureus in 5 min. Meanwhile, AgNPs@CEL exhibited remarkable photothermal antibacterial performance, which caused 6.2 and 6.1 log10 CFU/mL reduction of E. coli and S. aureus, with NIR irradiation for 5 min. Furthermore, the composite films prepared by doping only 0.5 wt% AgNPs@CEL into ethyl cellose could achieve a bactericidal rate more than 99.99 %. This study provides a new insight into design of controlled particle size lignin-based antibacterial nanosilver materials in a sustainable manner and holds promise for applications in antibacterial fields.
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Nanopartículas Metálicas , Prata , Prata/farmacologia , Lignina/farmacologia , Staphylococcus aureus , Escherichia coli , Ultrassom , Antibacterianos/farmacologia , Esterilização , Testes de Sensibilidade MicrobianaRESUMO
Thought-out utilization of entire lignocellulose is of great importance to achieving sustainable and cost-effective biorefineries. However, there is a trade-off between efficient carbohydrate utilization and lignin-to-chemical conversion yield. Here, we fractionate corn stover into a carbohydrate fraction with high enzymatic digestibility and reactive lignin with satisfactory catalytic depolymerization activity using a mild high-solid process with aqueous diethylamine (DEA). During the fractionation, in situ amination of lignin achieves extensive delignification, effective lignin stabilization, and dramatically reduced nonproductive adsorption of cellulase on the substrate. Furthermore, by designing a tandem fractionation-hydrogenolysis strategy, the dissolved lignin is depolymerized and aminated simultaneously to co-produce monophenolics and pyridine bases. The process represents the viable scheme of transforming real lignin into pyridine bases in high yield, resulting from the reactions between cleaved lignin side chains and amines. This work opens a promising approach to the efficient valorization of lignocellulose.
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Zinc sulfide is a promising high-capacity anode for practical sodium-ion batteries, considering its high capacity and the low cost of zinc and sulfur sources. However, the pulverization of particulate zinc sulfide causes active mass collapse and penetration-induced short circuits of batteries. Herein, a zinc sulfide encapsulated in a nitrogen-doped carbon shell (ZnS@NC) was developed for high-performance anodes. The confinement effect of nitrogen-doped carbon stabilizes the active mass structure during cycling thanks to the robust chemically and electronically bonded connections between nitrogen-doped carbon and zinc sulfide nanoparticles. Furthermore, the cycling stability of the ZnS@NC anode is boosted by the robust inorganic-rich solid electrolyte interphase (SEI) formed in cyclic and linear ether-based electrolytes. The ZnS@NC anode displayed a reversible specific capacity of 584 mAh g-1, an excellent rate capability of 327 mAh g-1 at 70 A g-1, and a highly stable cycling performance over 10000 cycles. This work provides a practical and promising approach to designing stable conversion anodes for high-performance sodium-ion batteries.
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Semiquinone (SQ) radicals play a critical role in the long-lasting UV-blocking application of lignin, while their origin and stable structure are unclear. Here, the organosolv lignin extracted from poplar (OL-P) is self-assembled into normal micelles (LNM) with more phenolic hydroxyl groups on the surface, and reverse micelles (LRM) with more methoxyl groups on the surface. After 12 h UV irradiation, the SQ radical contents in LNM and LRM increase 33% and 78% respectively. The performance of LNM based sunscreen keeps upswinging due to radical stabilization of phenolic hydroxyl groups. LRM based sunscreen experiences a gradual decrease after reaching maximum UV absorbance due to the quick generation and over oxidation of SQ radicals. Density functional theory (DFT) simulations reveal that methoxyl groups in OL-P has bigger bond length and smaller bond dissociation enthalpy than phenolic hydroxyl groups, and are easy to form SQ radicals. The Gibbs free energy (ΔG) needed for SQ-quinone transformation is above 26.10 kcal mol.-1 , while that for SQ-hydroquinone transformation is below -66.78 kcal mol.-1 . Hydroquinone is the stable structure of SQ radicals. This work discloses the origin and stable structure of SQ radicals in lignin under UV irradiation, and provides an important guidance for its long-lasting UV-blocking application.
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Achieving superior photomineralization of pollutants relies on a rational design of a dual S-scheme with a robust internal electric field (IEF). In this study, to tackle the low mineralization rate in type-II In2 O3 /In2 S3 (IO/IS) systems, an organic-inorganic dual S-scheme In2 O3 /PDI/In2 S3 (IO/PDI/IS) nanostructured photocatalyst is synthesized via a method combining solvent-induced self-assembly and electrostatic forces. Due to the unique energy band position and strong IEF, the photoinduced defect-transit dual S-scheme IO/PDI/IS facilitates the degradation of lignin and antibiotics. Notably, a promising mineralization rate of 80.9% for sodium lignosulfonate (SL) is achieved. The charge transport pathway of IO/PDI/IS are further validated through the analysis of in situ X-ray photoelectron spectroscopy (in situ XPS), density functional theory calculations, and radical trapping experiments. In-depth, two possible pathways for the photocatalytic degradation of lignin are proposed based on the intermediates monitored by liquid chromatography-mass spectrometry (LC-MS). This study presents a new strategy for the design of organic-inorganic dual S-scheme photocatalysts with a robust IEF for pollutant degradation.
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Its excellent renewability and biodegradability make cellulose an attractive resource to prepare fossil-based plastic alternatives. However, cellulose itself exhibits strong intermolecular hydrogen bond (H-bond) interactions, significantly restricting the mobility of cellulose chains, thus leading to poor thermo-processing performance. Here, we reconstructed the intermolecular interactions of cellulose chains via replacing the original H-bonds with dynamic covalent bonds. By this, cellulose can be easily thermo-processed into a cellulosic plastic under mild conditions (70 °C). Through adjusting the chemical structure of dynamic covalent networks, the cellulosic plastic shows tunable mechanical strength (3.0-33.5 MPa) and toughness (43-321 kJ m-2). The cellulosic plastic also exhibits excellent resistance to water, organic solvent, acid solution, alkali solution, and high temperature (>400 °C). Moreover, it owns good chemical and biological degradability and recyclability. This work provides an effective method to develop high-performance cellulosic plastics for fossil-based plastic substitution.
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Flocculation is a common process for wastewater treatment. However, the most commonly used organic synthetic flocculants such as polyacrylamide are petroleum-based. In this work, biomass lignin was grafted with cationic starch to synthesize low-cost, green and fully biomass-based multifunctional flocculants. The cationic polyacrylamide was replaced by cheap industrial cationic starch. Hyperbranched multifunctional lignin-grafted cationic starch flocculant (CS-L) was successfully prepared via ring-opening reaction with epichlorohydrin. The mass content of lignin in the grafted product was between 16.6 % and 70.1 %. With the dosage of CS-L between 4.0 and 7.5 mg/l, the turbidity removal rate for 500 mg/l kaolin suspension reached more than 97 %. When the dosage of CS-L was 24 mg/l, the removal rate of 50 mg/l Cu2+ reached 85.7 %. Importantly, when the mixed solution of kaolin particles and Cu2+ was treated, the synchronous removal rates of kaolin and Cu2+ reached 90 % and 72 % respectively in the range of 8.0-12.0 mg/l flocculant addition. The synthesized lignin-grafted cationic starch flocculant showed an excellent multifunctional flocculation function.
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Amido , Purificação da Água , Lignina , Caulim , Biomassa , Floculação , CátionsRESUMO
In this study, a porous polyamine lignin microsphere (PPALM) was prepared through the inverse suspension polymerization combined with freeze-drying, during which sodium lignosulfonate and polyetheramine (PEA) were crosslinked with epichlorohydrin (ECH) as the cross-linker. By adjusting the amount of ECH and PEA, the optimized PPALM exhibited suitable crosslinking degree, ensuring a balance of framework flexibility and rigidity, thereby facilitating the formation of abundant and fine pores. PPALM demonstrated good mechanical properties comparable to commercial sulfonated polystyrene cationic resin, with a porosity of 61.12 % and an average pore size of 283.51 nm. The saturation adsorption capacity of PPALM for Pb2+ was measured to be 156.82 mg/g, and it remained above 120 mg/g after five cycles of regeneration. Particularly, the concentration of 50 mg/L Pb2+ solution could be reduced to 0.98 mg/L after flowing through the PPALM packed bed, indicating the great potential of PPALM for application in wastewater treatment.
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Lignina , Poluentes Químicos da Água , Adsorção , Porosidade , Microesferas , ChumboRESUMO
BNNS (boron nitride nanosheets)-CNF (cellulose nanofibrils) nanocomposite films have attracted increasing attention for advanced thermal management applications. However, the nanocomposite films reported so far generally suffer from unsatisfactory overall performance, especially for thermal conductivity and tensile strength. In this work, a nanocomposite film with excellent overall performance was prepared by using CCNF1.2 (carboxymethylated CNF with 1.2 mmol·g-1 carboxyl content) simultaneously as effective dispersant and reinforcement matrix for BNNS. The high aspect ratio of CCNF1.2 is primarily responsible for its excellent dispersion capability for BNNS, which provides strong steric hindrance repulsion force. Meanwhile, CCNF1.2 manifests the strongest hydrophobic-hydrophobic interactions with BNNS, and its carboxyl groups completely interact with the -OH of BNNS by hydrogen bonding. As a result, the BNNS-CCNF1.2 film (50 wt% BNNS) exhibits compacted aligned structure and superior comprehensive performance (125.0 MPa tensile strength, 17.3 W·m-1·K-1 in-plane thermal conductivity, and improved water resistance). This work demonstrates the effectiveness of CCNF in improving the overall performance of BNNS-CNF films and paves the way for their practical application in the advanced thermal management of next-generation electronic devices.