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1.
Adv Mater ; : e2403876, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38739951

RESUMEN

Sorption-based atmospheric water harvesting is an attractive technology for exploiting unconventional water sources. A critical challenge is how to facilitate fast and continuous collection of potable water from air. Here, a bio-based gel (CAL gel), resulting from the integration of a whole biomass-derived polymer network with lithium chloride is reported. A fast adsorption/desorption kinetics, with a water capture rate of 1.74 kg kg-1 h-1 at 30% relative humidity and a desorption rate of 1.98 kg kg-1 h-1, was simultaneously realized in one piece of CAL gel, because of its strong hygroscopicity, hydrophilic network, abundant water transport channels, photothermal conversion ability, and ∼200-µm-thick self-supporting bulky structure caused by multicomponent synergy. A solar-driven, drum-type, tunable, and portable harvester is designed that can harvest atmospheric water within a brief time. Under outdoor conditions, the harvester with CAL gels operates 36 switches (180°) per day realizes a water yield of 8.96 kg kggel -1 (18.87 g kgdevice -1). This portable harvester highlights the potential for fast and scalable atmospheric water harvesting in extreme environments. This article is protected by copyright. All rights reserved.

2.
Carbohydr Polym ; 336: 122109, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38670767

RESUMEN

Pulp and paper are gradually transforming from a traditional industry into a new green strategic industry. In parallel, cellulose-derived transparent paper is gaining ground for the development of advanced functional materials for light management with eco-friendly, high performance, and multifunctionality. This review focuses on methods and processes for the preparation of cellulose-derived transparent papers, highlighting the characterization of raw materials linked to responses to different properties, such as optical and mechanical properties. The applications in electronic devices, energy conversion and storage, and eco-friendly packaging are also highlighted with the objective to showcase the untapped potential of cellulose-derived transparent paper, challenging the prevailing notion that paper is merely a daily life product. Finally, the challenges and propose future directions for the development of cellulose-derived transparent paper are identified.

3.
Chem Sci ; 15(11): 3920-3927, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38487249

RESUMEN

Stimuli-responsive aggregation-induced emission (AIE) materials are highly sensitive and rapidly responsive to external signals, making them ideal solid materials for anti-counterfeiting encryption. However, the limited conformational and packing variations resulting from regio-isomerization with a single substituent restricts the stimuli-responsive behavior of these materials. In this work, several AIE-active regio-structural isomers based on the salicylaldehyde Schiff base scaffold have been straightforwardly obtained through multiple substitutions with bromide and triphenylamine moieties. Solvent-effect experiments demonstrate their different orders of charge-transfer and excited-state intramolecular proton transfer upon photoexcitation, indicating the regulation of excited-state processes via multi-site isomerization. These isomers also demonstrate mechanochromism and acidichromism, allowing for adjustable stimuli-responsive effects. As a demonstration, p-Br-TPA with both mechanochromism and acidichromism can be synergistically utilized for multi-level decryption. This study successfully regulates the evolution of excited states through multi-site isomerization, offering a general approach for achieving tunable stimuli-responsive properties in AIE-active salicylaldehyde Schiff bases toward multi-level decryption.

4.
Phytomedicine ; 127: 155474, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38471369

RESUMEN

BACKGROUND: Inflammatory bowel disease (IBD) is characterized by a chronic inflammation of the intestine, which significantly affects patients' quality of life. As a perennial plant with the homology of medicine and food, Panax ginseng is known for its substantial anti-inflammatory effects in various inflammatory disorders. Ginsenosides, the main bioactive compounds of P. ginseng, are recognized for their efficacy in ameliorating inflammation. PURPOSE: Over the past decade, approximately 150 studies have investigated the effects of P. ginseng and ginsenosides on IBD treatment and new issues have arisen. However, there has yet to be a comprehensive review assessing the potential roles of ginsenosides in IBD therapy. METHOD: This manuscript strictly adheres to the PRISMA guidelines, thereby guaranteeing systematic synthesis of data. The research articles referenced were sourced from major scientific databases, including Google Scholar, PubMed, and Web of Science. The search strategy employed keywords such as "ginsenoside", "IBD", "colitis", "UC", "inflammation", "gut microbiota", and "intestinal barrier". For image creation, Figdraw 2.0 was methodically employed. RESULTS: Treatment with various ginsenosides markedly alleviated clinical IBD symptoms. These compounds have been observed to restore intestinal epithelia, modulate cellular immunity, regulate gut microbiota, and suppress inflammatory signaling pathways. CONCLUSION: An increasing body of research supports the potential of ginsenosides in treating IBD. Ginsenosides have emerged as promising therapeutic agents for IBD, attributed to their remarkable efficacy, safety, and absence of side effects. Nevertheless, their limited bioavailability presents a substantial challenge. Thus, efforts to enhance the bioavailability of ginsenosides represent a crucial and promising direction for future IBD research.


Asunto(s)
Ginsenósidos , Enfermedades Inflamatorias del Intestino , Panax , Humanos , Ginsenósidos/farmacología , Ginsenósidos/uso terapéutico , Calidad de Vida , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Inflamación/tratamiento farmacológico
5.
Carbohydr Polym ; 334: 122034, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38553233

RESUMEN

Cryogels that are constructed with cellulose nanofibrils (CNF) are important as green materials for a wide range of applications. However, their utilization is limited by inherent hydrophilicity and insufficient mechanical properties. Herein, a processable CNF/nanochitin (NCh)-stabilized Pickering emulsion that contains polylactide (PLA) in the oil phase is developed to directly produce ternary composite cryogels via freeze-drying. The complexation of CNF with NCh promotes CNF adsorption at the surface of PLA droplets, resulting in formation of uniform Pickering PLA droplets. The CNF/NCh complex-stabilized PLA droplets are easy to be translated to the internal structure of the cryogels, exhibiting lightweight nature and possessing highly porous structure. The interconnected network and lamellar structure formed by the CNF/NCh complexes, associating with inclusion of PLA particles, improve the cryogel structure integrity upon post-processing and endow hydrophilic cryogel with water resistance. This study offers a straightforward and eco-friendly Pickering emulsion template on fabrication of the CNF-based composite cryogel with controllable microstructure and mechanical performance, broadening construction of nanocellulose-based composites.

6.
Int J Biol Macromol ; 262(Pt 1): 130017, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38336333

RESUMEN

Sustainably sourced lignin presents great potential as a green feedstock for fertilizer production but commercial fulfillment is still challenging owing to the mediocre fertilizer activity of lignin. To address this issue, an effective strategy to enhance the activity of lignin-based potassium fertilizer (LPF) is proposed through lignin fractionation. Three lignin fractions subdivided from enzymatic hydrolysis lignin (EHL) were adopted as the feedstock for LPF preparation, and the effect of lignin fractionation on wheat seed germination and seedling growth was investigated. Compared with the potassium fertilizer from unfractionated lignin, LPF-F1 showed significantly improved effects on promoting seed germination and seedling growth, which can be attributed to the high potassium content resulted from its abundant phenolic hydroxyl and carboxyl contents. Under the optimal treatment concentration (100 mg/L), LPF-F1 showed comparable promotion effect to commercial fulvic acid potassium on wheat seedling growth, suggesting the potential of LPF-F1 as commercial potassium fertilizer. Overall, this work reveals that lignin heterogeneity presents critical effects on the wheat seed germination and seedling growth of LPF, and the fertilizer activity of LPF can be substantially improved using fractionated lignin with low molecular weight as the raw material.


Asunto(s)
Lignina , Plantones , Lignina/farmacología , Germinación , Triticum , Fertilizantes , Hidrólisis , Semillas
7.
Chemosphere ; 352: 141365, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38331267

RESUMEN

Microplastics (MPs), as emerging pollutants, have attracted the attention of environmentalists, statespersons, and the scientific community over the last few decades. To address the spread of MPs in the environment, it is imperative to develop various removal techniques and materials that are effective, scalable, and ecologically benign. However, to the best of our knowledge, no review has systematically examined the removal of MPs using adsorption or provided an in-depth discussion on various adsorbents. Adsorption is an inexpensive and effective technology for wastewater treatment. Recently, many researchers have conducted studies on MP remediation using diverse adsorbent materials, such as biochar, activated carbon, sponges, carbon nanotubes, metal-layered oxides, metal-organic frameworks (MOFs), and zeolites. Each adsorbent has advantages and disadvantages. To overcome their disadvantages, researchers have been designing and developing hybrid adsorbents for MP remediation. This review provides insights into these individual adsorbents and also discusses hybrid adsorbents for MP removal. Finally, the review elaborates on future possibilities and ways to enable more efficient, scalable, and environmentally friendly MP cleanup. Overall, this review bridges the gap between contemporary MP remediation using adsorption techniques and adsorbent development.


Asunto(s)
Contaminantes Ambientales , Nanotubos de Carbono , Contaminantes Químicos del Agua , Purificación del Agua , Agua , Contaminantes Químicos del Agua/análisis , Plásticos , Microplásticos , Adsorción , Óxidos , Purificación del Agua/métodos
8.
J Colloid Interface Sci ; 659: 374-384, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38181701

RESUMEN

Lignin-derived carbon materials are widely used as electrode materials for supercapacitors. However, the electrochemical performance of these materials is limited by the surface chemistry and pore structure characteristics. Herein, a novel and sustainable strategy was proposed to prepare heteroatom-doped lignin-derived carbon material (Fe-NLC) with well-developed pore size distributions and enhanced graphitization structure via a facile lignin-Fe coordination method followed by carbonization. During carbonization, Fe3+ in lignin-metal complexes evolve into nanoparticles, which act as templates to introduce porous structures in carbon materials. Also, the lignin-Fe coordination structure endows the material with a higher graphitization during carbonization, thereby improving the structural properties of the carbon materials. Due to the removal of Fe3O4 template, the obtained Fe-NLC possessed reasonable pore distribution and nitrigen/oxygen (N/O) functional groups, which can improve the wettability of materials and introduce pseudocapacitance. Accordingly, Fe-NLC possesses a notable specific capacitance of 264 F/g at 0.5 A/g. Furthermore, a symmetric supercapacitor Fe-NLC//Fe-NLC with a high voltage window (1.8 V) was constructed. The symmetric supercapacitor exhibits a maximum energy density of 15.97 Wh/kg at 450 W/kg, demonstrating well application prospects. This paper proposes a novel approach for preparing carbon materials via lignin-metal coordination to provide an alternative way to explore sustainable and low-cost energy storage materials.

9.
Int J Biol Macromol ; 258(Pt 2): 129132, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38171433

RESUMEN

Adhesives are used extensively in the wood industry. As resource and environmental issues become increasingly severe, the development of green and sustainable biomass-based adhesives has attracted increasing attention. In this work, a green wood adhesive is developed from poly(vinyl alcohol) and lignin with molecular designs of lignin extending beyond those in nature. The lignin undergoes extraction from corncob residue, aldehydration, and phenolisation (phenol, resorcinol, and catechol) to significantly increase the phenolic hydroxyl groups (over 7.92 mmol/g), which has the effect of enhancing the hydrogen bonding force between the adhesive and the wood, thereby greatly improving adhesive performance. Compared with pure PVA, polyphenol lignin-containing PVA showed improved adhesion strength and hydrophobicity. PVA/resorcinol-lignin has the significantly improved wood lap shear strength (6.27 MPa, 77.6 % improvement) and hydrophobicity (almost 100 % increase in wet shear strength). This research not only provides a green and high-performance alternative raw material for wood adhesives but also broadens the path for large-scale application of biomass.


Asunto(s)
Lignina , Polifenoles , Polifenoles/análisis , Lignina/química , Alcohol Polivinílico , Adhesivos/química , Madera/química , Fenoles/química , Metanol , Cloruro de Polivinilo , Resorcinoles
10.
Int J Biol Macromol ; 258(Pt 1): 128640, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38061515

RESUMEN

Pectin-crosslinked gum ghatti hydrogel (PGH) has been synthesized utilizing pectin and gum ghatti through an uncomplicated and inexpensive copolymerization method. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM-elemental mapping), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS) characterization techniques have been employed to determine various structural, chemical and compositional characteristics of fabricated PGH. Three different weight ratios (1:1, 2:1, or 1:2 for pectin and gum ghatti, respectively) were employed to synthesize three distinct types of PGH. Swelling studies has been done to determine the best ratios for PGH fabrication. PGH has been assessed as an adsorbent for the removal of malachite green dye from aqueous solutions. The effects of PGH dosage (100-400 mg/L), dye concentration (10-160 mg/L), pH (2-9 pH), adsorption time (0-480 min), and temperature (25-55 °C) has been examined through batch solutions. According to Langmuir isotherm analysis, the maximum adsorption capacity is 658.1 mg/g. By using pseudo-second-order kinetics and the Freundlich adsorption isotherm, the adsorption process could be well explained. After five consecutive cycles, PGH had an adsorption percentage of 86.917 % for the malachite green dye. It is safe for the environment and may be used to remove malachite green (MG) dye from aqueous solutions.


Asunto(s)
Hidrogeles , Gomas de Plantas , Colorantes de Rosanilina , Contaminantes Químicos del Agua , Hidrogeles/química , Adsorción , Pectinas , Espectroscopía Infrarroja por Transformada de Fourier , Cinética , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/química
11.
Small ; 20(17): e2307344, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38133516

RESUMEN

The intrinsic poor rheological properties of MXene inks result in the MXene nanosheets in dried MXene microfibers prone to self-stacking, which is not conducive to ion transport and diffusion, thus affecting the electrochemical performance of fiber-based supercapacitors. Herein, robust cellulose nanofibrils (CNF)/MXene hybrid fibers with high electrical conductivity (916.0 S cm-1) and narrowly distributed mesopores are developed by wet spinning. The interfacial interaction between CNF and MXene can be enhanced by hydrogen bonding and electrostatic interaction due to their rich surface functional groups. The interfacial modulation of MXene by CNF can not only regulate the rheology of MXene spinning dispersion, but also enhance the mechanical strength. Furthermore, the interlayer distance and self-stacking effect of MXene nanosheets are also regulated. Thus, the ion transport path within the fiber material is optimized and ion transport is accelerated. In H2SO4 electrolyte, a volumetric specific capacitance of up to 1457.0 F cm-3 (1.5 A cm-3) and reversible charge/discharge stability are demonstrated. Intriguingly, the assembled supercapacitors exhibit a high-volume energy density of 30.1 mWh cm-3 at 40.0 mW cm-3. Moreover, the device shows excellent flexibility and cycling stability, maintaining 83% of its initial capacitance after 10 000 charge/discharge cycles. Practical energy supply applications (Power for LED and electronic watch) can be realized.

12.
Int J Biol Macromol ; 258(Pt 2): 129046, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38154714

RESUMEN

Constructing a high-performance ultraviolet shielding film is an effective way for addressing the growing problem of ultraviolet radiation. However, it is still a great challenge to achieve a combination of multifunctional, excellent mechanical properties and low cost. Here, inspired by the multiscale structure of biomaterials and features of lignin, a multifunctional composite film (CNF/CMF/Lig-Ag) is constructed via a facile vacuum-filtration method by introducing micron-sized cellulose fibers (CMF) and lignin-silver nanoparticles (Lig-Ag NPs) into the cellulose nanofibers (CNF) film network. In this composite film, the microfibers interweave with nanofibers to form a multiscale three-dimensional network, which ensures satisfactory mechanical properties of the composite film. Meanwhile, the Lig-Ag NPs are employed as a multifunctional filler to enhance the composite film's antioxidant, antibacterial and ultraviolet shielding abilities. As a result, the prepared CNF/CMF/Lig-Ag composite film demonstrates excellent mechanical properties (with tensile strength of 133.8 MPa and fracture strain of 7.4 %), good biocompatibility, high thermal stability, potent antioxidant and antibacterial properties. More importantly, such composite film achieves a high ultraviolet shielding rate of 98.2 % for ultraviolet radiation A (UVA) and 99.4 % for ultraviolet radiation B (UVB), respectively. Therefore, the prepared CNF/CMF/Lig-Ag composite film shows great potential in application of ultraviolet protection.


Asunto(s)
Lignina , Nanopartículas del Metal , Lignina/química , Celulosa/química , Plata/química , Antioxidantes , Rayos Ultravioleta , Nanopartículas del Metal/química , Antibacterianos
13.
Int J Biol Macromol ; 258(Pt 2): 128963, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38154721

RESUMEN

Nano-lignin presents great potential in advanced carbon materials preparation since it integrates the advantages of nanomaterials as well the preferable properties of lignin (e.g. high carbon content and highly aromatic structure). Herein, lignin-derived carbon nanosphere supported Pd catalysts (Pd@LCNS) were prepared via a two-step carbonization of Pd2+ adsorbed lignin nanospheres (LNS) and applied in vanillin hydrodeoxygenation. The effect lignin heterogeneity on the synthesis of Pd@LCNS as well as its catalytic performance was further investigated through the synthesis of Pd@LCNS using three lignin fractions with different molecular weight. The results showed that the three Pd@LCNSs exhibited significant differences in the morphology of both carbon support and Pd nanoparticles. Pd@LCNS-3 prepared from high molecular weight lignin fraction (L-3) presented stable carbon nanosphere support with the smallest particle size (∼150 nm) and the highest Pd loading amount (3.78 %) with the smallest Pd NPs size (∼1.6 nm). Therefore, Pd@LCNS-3 displayed superior catalytic activity for vanillin hydrodeoxygenation (99.34 % of vanillin conversion and 99.47 % of 2-methoxy-4-methylphenol selectivity) at 90 °C without H2. Consequently, this work provides a sustainable strategy to prepare uniformly dispersed lignin-based carbon-supported Pd catalyst using high molecular weight lignin as the feedstock and further demonstrate its superior applicability in the selective transfer hydrogenation of vanillin.


Asunto(s)
Benzaldehídos , Carbono , Nanosferas , Carbono/química , Lignina/química , Hidrogenación
14.
Int J Biol Macromol ; 253(Pt 3): 126903, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37714239

RESUMEN

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.


Asunto(s)
Grafito , Carbono , Conductividad Eléctrica , Electrónica , Hidrogeles
15.
Int J Biol Macromol ; 244: 125326, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37302625

RESUMEN

As a renewable and low-cost biomacromolecule with high aromaticity and carbon content, lignin is a promising raw material for preparation of versatile carbon materials. Herein, we present a facile one-pot approach to prepare PdZn alloy nanocluster catalysts supported on N-doped lignin-derived nanolayer carbon through facile pyrolysis of melamine-mixed lignin-Pd-Zn complex. The dispersion of the PdZn alloy nanoclusters could be effectively modulated by varying the addition of melamine and the molar ratio of Pd and Zn salts. PdZn alloy nanocluster catalysts (Pd-Zn29@N10C) with ultra-small particle size (about 0.47 nm) were prepared when 10 times of melamine (relative to lignin weight) was added and the molar ratio of Pd and Zn salts was 1:29. Thereby, the catalyst presented superior catalytic activity for reduction of Cr(VI) to harmfulless Cr(III), significantly better than the two references Zn@N10C (without Pd addition) and Pd-Zn29@C (without N doping), as well as the commercial Pd/C. In addition, thanks to the strong anchoring of the PdZn alloy on the N-doped nanolayer support, the Pd-Zn29@N10C catalysts also exhibited good reusability. Consequently, the current study provides a straightforward and feasible method for producing highly dispersed PdZn alloy nanoclusters by lignin coordination, and further demonstrates its excellent applicability in hexavalent chromium reduction.


Asunto(s)
Aleaciones , Lignina , Carbono , Sales (Química)
16.
ChemSusChem ; 16(15): e202300174, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37338272

RESUMEN

Traditionally, phenols used to prepare phenol-formaldehyde (PF) resin adhesives are obtained from phenolic compounds and various chemicals, which are extracted from petroleum-based raw materials. Lignin, a sustainable phenolic macromolecule in the cell wall of biomass with an aromatic ring and a phenolic hydroxyl group similar to those of phenol, can be an ideal substitute for phenol in PF resin adhesives. However, only a few lignin-based adhesives are produced on a large scale in industry, mainly because of the low activity of lignin. Preparing lignin-based PF resin adhesives with exceptional achievements by modifying lignin instead of phenol is an efficient method to improve the economic benefits and protect the environment. In this review, the latest progress in the preparation of PF resin adhesives via lignin modification, including chemical, physical, and biological modifications, is discussed. In addition, the advantages and disadvantages of different lignin modification methods for adhesives are compared and discussed, and future research directions for the synthesis of lignin-based PF resin adhesives are proposed.

17.
Int J Biol Macromol ; 242(Pt 1): 124773, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37150369

RESUMEN

The increasing depletion of oil resources and the environmental problems caused by using much fossil energy in the rapid development of society. The bio-oil becomes a promising alternative energy source to fossil. However, bio-oil cannot be directly utilized, owing to its high proportion of oxygenated compounds with low calorific value and poor thermal stability. Catalytic hydrodeoxygenation (HDO) is one of the most effective methods for refining oxygenated compounds from bio-oil. HDO catalysts play a crucial role in the HDO reaction. This review emphasizes the description of the main processing of HDO and various catalytic systems for bio-oil, including noble/non-noble metal catalysts, porous organic polymer catalysts, and polar solvents. A discussion based on recent studies and evaluations of different catalytic materials and mechanisms is considered. Finally, the challenges and future opportunities for the development of catalytic hydrodeoxygenation for bio-oil upgradation are looked forward.


Asunto(s)
Biocombustibles , Calor , Biomasa , Catálisis
19.
Nanomicro Lett ; 15(1): 98, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37038023

RESUMEN

Multifunctional architecture with intriguing structural design is highly desired for realizing the promising performances in wearable sensors and flexible energy storage devices. Cellulose nanofiber (CNF) is employed for assisting in building conductive, hyperelastic, and ultralight Ti3C2Tx MXene hybrid aerogels with oriented tracheid-like texture. The biomimetic hybrid aerogels are constructed by a facile bidirectional freezing strategy with CNF, carbon nanotube (CNT), and MXene based on synergistic electrostatic interaction and hydrogen bonding. Entangled CNF and CNT "mortars" bonded with MXene "bricks" of the tracheid structure produce good interfacial binding, and superior mechanical strength (up to 80% compressibility and extraordinary fatigue resistance of 1000 cycles at 50% strain). Benefiting from the biomimetic texture, CNF/CNT/MXene aerogel shows ultralow density of 7.48 mg cm-3 and excellent electrical conductivity (~ 2400 S m-1). Used as pressure sensors, such aerogels exhibit appealing sensitivity performance with the linear sensitivity up to 817.3 kPa-1, which affords their application in monitoring body surface information and detecting human motion. Furthermore, the aerogels can also act as electrode materials of compressive solid-state supercapacitors that reveal satisfactory electrochemical performance (849.2 mF cm-2 at 0.8 mA cm-2) and superior long cycle compression performance (88% after 10,000 cycles at a compressive strain of 30%).

20.
Int J Biol Macromol ; 234: 123603, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36775225

RESUMEN

The conversion of renewable lignin with low-cost and high carbon content properties into porous carbon materials for supercapacitor applications has caught considerable interest. Herein, two dimensional lignin-derived carbon nanosheets (N-LHPC) with hierarchically porous structures were facilely synthesized via a novel metal-lignin assembly strategy and their performances for supercapacitor applications were investigated. During the carbonization process, the uniformly distributed Zn facilitates the coordinating development of micropores structure and the generated MgO embedded in the carbon matrix acts as a template to produce mesoporous structure after acid washing. Moreover, the melamine addition promotes the development of mesopores by formation of lamellae structure and realizes the N doping in the carbon materials. Therefore, the obtained N-LHPC presents an excellent specific capacitance of 235.75 F/g at 0.5 A/g owing to its hierarchical pore structure as well as the N/O functional groups. Moreover, at the power density of 450 W/kg, the N-LHPC achieves a maximum energy density of 14.75 Wh/kg, showing great application potential in energy storage. The metal-lignin assembly strategy followed by N-doping proposed in this paper provides N-LHPC materials with hierarchical nanostructure, good electron/ion transfer properties, and abundant pseudocapacitive active species, which improve the capacitance performances of the N-LHPC.


Asunto(s)
Carbono , Lignina , Porosidad , Capacidad Eléctrica , Transporte de Electrón , Metales
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