Advanced Composites and Hybrid Materials最新文献

Carbon materials have emerged as a rapidly advancing category of high-performance materials that have garnered significant attention across various scientific and technological disciplines. Their exceptional biochemical properties render them highly suitable for diverse biomedical applications, including implantation, artificial joints, bioimaging, tissue and bone engineering, and scaffold fabrication. However, a more systematic approach is required to fully exploit the potential of carbon-based materials in the biomedical realm, necessitating extensive and collaborative research to address the existing challenges, which comprehensive long-term stability studies, the surface properties and investigate the toxicity of biomedical materials. This review paper aims to provide a comprehensive overview of carbon materials, elucidating their inherent advantages and highlighting their increasingly prominent role in biomedical applications. After a brief introduction of carbonaceous materials, we discuss innovative deposition strategies that can be utilized to artificially replicate desired properties, such as biocompatibility and toxicology, within complex structures. Further, this paper serves as a valuable resource to harness the potential of carbon materials in the realm of biomedical applications. Last, we conclude with a discussion on the significance of continuous exploration in propelling further advancements within this captivating field.

Conductive ionic liquid electrolytes have attracted increasing attention because of their remarkable energy harvesting and storage characteristics for utilization in triboelectric nanogenerators and energy storage devices, respectively. Especially, the ionic conductive liquid electrolyte-based energy harvesting device that can operate with high efficiency and stability in harsh temperature conditions is greatly needed for urgent rescue and wilderness exploration. Herein, the dual-function nature of carboxymethyl cellulose (CMC), water, and glycerol was employed as an electrolyte as well as an electrical conductor for single-electrode triboelectric nanogenerator (TENG) and supercapacitor applications. The biocompatible ionic liquid electrode-based single-electrode TENG (LSE-TENG) exhibits superior performance with an optimized CMC concentration of 3 wt%. Furthermore, by incorporating an additional ionic compound (NaCl) in the optimized CMC-based ionic liquid solutions, the performance of the LSE-TENG and the electrochemical properties are largely enhanced. With the anti-freezing and anti-dehydration properties of glycerol, the fabricated LSE-TENG delivers stable electrical output performance in the low temperature (−20 °C) to high temperature (70 °C) range. The power density of the 3 wt% NaCl-based LSE-TENG increases by 11 folds as compared to the CMC-based LSE-TENG. In addition, the LSE-TENG is integrated with a sensor for anti-theft applications. The present study demonstrates an innovative engineering technology for fabricating high-performance TENGs that can prove enormous interest in flexible and wearable applications.

Abstract

This work provides an innovative method for preparing different isomerization catalysts by impregnating different proportions of MgCl₂ and AlCl₃ and combining different K compounds on cellulose-derived biochar, followed by pyrolysis. Results show MgO and Al(OH)₃ existing in ₄Mg-₁Al-C catalyst can obtain better catalytic effect on glucose isomerization than the singe of Al presenting in ₀Mg-₁Al-C catalyst. Moreover, the synergism effects of the multi-catalytic active sites such as β-_, γ-Al(OH)₃, KCl, MgO, and K₄H₂(CO₃)₃ in Mg-Al-KHCO₃-C catalyst can further lead to an increase in glucose isomerization, compared to the ₄Mg-₁Al-C catalyst. The X-ray diffraction results present that the value of O/Al in Mg-Al-KHCO₃-C catalyst is as high as 13.38, which provides many unsaturated acidic catalysis sites and benefits the glucose isomerization. Simultaneously, the TPD results reveal that the main active sites (MgO, Al(OH)₃, and K₄H₂(CO₃)₃) in Mg-Al-KHCO₃-C catalyst can provide weakly acidic and basic sites and avoid strongly acidic and basic sites to excessively attack the glucose. Based on the DFT analysis, the results indicate that the MgO has a great effect on the ring-opening reaction to form acyclic glucose, while Al(OH)³⁺ has a great effect on promoting acyclic glucose hydrogen transfer isomerized to form fructose. Compared to other carbon-based metal catalysts, the prepared Mg-Al-KHCO₃-C has excellent catalytic performance, which gives a higher fructose yield (38.7%) and selectivity (87.72%) and glucose conversion (44.12%) at 100 °C in 30 min. In this study, we develop a highly efficient Mg-Al-K-biochar catalyst for glucose isomerization and provide an efficient method for cellulose valorization.

Abstract

Perfluorooctanoic acid (PFOA) is a highly persistent organic pollutant of global concern. A novel nanocomposite composed of ZnO nanoparticles and citric acid-modified g-C₃N₄ was synthesized by ball milling process. The synthesized nanocomposite was more efficient than pure ball-milled ZnO nanoparticles for PFOA elimination under visible light irradiation. The optimal hybrid photocatalyst, produced by the addition of 5 wt% of citric acid-modified g-C₃N₄, demonstrated significantly better performance for PFOA removal than pure ZnO nanoparticles under UV irradiation, with the apparent rate constants of 0.468 h⁻¹ and 0.097 h⁻¹, respectively. The addition of peroxymonosulfate (0.53 g L⁻¹) significantly increased PFOA removal, clarifying the crucial effect of sulfate radicals on PFOA photodegradation. In comparison, citric acid-modified g-C₃N₄ was not effective for PFOA elimination under visible light irradiation, even with the addition of peroxymonosulfate. Further experiments under dark conditions identified surface adsorption on hybrid photocatalyst as a key process in total PFOA removal. In summary, PFOA removal by ZnO@citric acid-modified graphitic carbon nitride nanocomposites is due to the combined action from adsorption and photodegradation, with adsorption as the dominating mechanism.

Desalination with solar-driven photothermal evaporator is extremely attractive for tackling the current freshwater shortage of humanity, and a scalable and efficient interfacial solar evaporator is thus highly desirable. In this work, a facile low-cost Janus evaporator with excellent evaporation performance and energy conversion performance was fabricated from potassium hydroxide (KOH)–activated lignin-based carbon (KLC) and commercial melamine foam (MF). The KLC with rich and multiple microscale/nanoscale pores presented high light absorption (90%) and excellent photothermal conversion capacity (up to 60.4 °C) in the full solar spectrum (200–2500 nm). Subsequently, the KLC was simply coated on the upper surface of MF to obtain the self-floating Janus KLC/MF evaporator. The hydrophilic nature and the porous structure of MF ensured sufficient water supply to the evaporation interface and facilitated effective diffusion of water vapor. The solar steam generation test revealed that the water evaporation rate of the Janus KLC/MF under simulated sunlight was 1.539 kg m⁻² h⁻¹, with a superior photothermal conversion efficiency of 95.88%, which is higher than previously reported melamine-framed evaporators. Moreover, the evaporator has an excellent recycling ability and shows a stable water evaporation rate, indicating preferable durability in practical desalination. Overall, this work demonstrates the great potential of using low-cost lignin as a feedstock for the preparation of solar-driven interfacial evaporation systems integrating multiple functionalities for clean water production and thus offers a viable strategy for the application of lignin-based functional materials.

Abstract

Lignin has gained extensive attention as an ideal carbon precursor due to its abundance and high carbon content. However, the agglomeration of lignin and additional corrosive and unrecyclable reagents in direct pyrolysis still limit the development of lignin-based porous carbons. Herein, a facile and eco-friendly strategy was proposed to fabricate hierarchical porous lignin/cellulose-based carbon materials (LCs). In the process, cellulose nanofibrils acted as the skeleton of the bio-aerogels, which supported lignin and benefit the preparation of the LCs. Moreover, the specific surface area and the graphitization degree of LCs can be regulated by varying the cellulose content. Without activation, the bio-based carbon material (LC30) had a high specific surface area of 1770 m² g⁻¹, which displayed high specific capacitance of 216.2 F g⁻¹ at the current density of 0.5 A g⁻¹. The supercapacitor based on LC30 also showed outstanding energy density of 12.3 Wh kg⁻¹ at the power density of 50 W kg⁻¹. The sustainable raw material, simple and harmless preparation process, and remarkable electrochemical performance enable LC30, a promising supercapacitor electrode for energy storage.

Abstract

Slow oxygen evolution reaction (OER) and material transport impedance in catalyst-coated membrane (CCM) are major challenges for the practical proton exchange membrane water electrolyzer (PEMWE). Herein, we present a novel OER catalyst by polyether-derived composite oxide pyrolysis with a multilevel porous support and abundant oxygen vacancies to boost efficiency and durability in water electrolysis. The formation of a heterointerface with abundant oxygen vacancies in IrO_x improves the catalytic activity and prevents IrO_x from peroxidation. Furthermore, the unique pore structure of the support facilitates the mass transport of the anode catalyst layer during water electrolysis at high current density, and the mass transport resistance of the water electrolyzer is only 0.0154 Ω cm² at 1.5 A cm⁻². When used in a PEMWE, the prepared electrocatalysts have an impressive electrochemical performance of 1.87 V at 3·A cm⁻² with an Ir loading of only 0.91 mg cm⁻². This approach highlights the importance of oxygen vacancies and transportation in the catalyst-support interface, providing a promising solution for high-rate practical water electrolysis.

Using biomass waste materials to prepare electrode materials with excellent properties is an effective strategy for solving current energy and environmental problems. In this work, coffee grounds were pretreated with Co(NO₃)₂ and Ni(NO₃)₂, then KOH was used to activate the pretreated coffee grounds at a high temperature to obtain a foam-like electrode material with interconnected microporous-mesoporous-macroporous hierarchical channels. This preparation method is simple and has low energy consumption, and the resulting material has an ultra-low internal resistance of 0.31 Ω. The specific capacitance of CGC-2 is 302.65 F g⁻¹ at a current density of 1 A g⁻¹. The low internal resistance and high electrical conductivity of this activated material are attributed to the presence of Co²⁺ and Ni²⁺ during carbonization, whose catalytic effect leads to a relatively ordered lattice structure. The interconnected structure of the final product is mainly caused by the strong activation function of KOH generating many pores. The prepared material exhibits good rate performance and cycling stability, and it has a Coulombic efficiency of nearly 93%. This work provides a novel idea for using biomass materials to fabricate high-performance electrode materials for supercapacitors.

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Abstract

This study focuses on investigating the microstructural architecture of bioinspired hierarchical graphene nanoplatelets-(GnPs) and glass fiber-(GF) reinforced polypropylene-based hybrid composites and its impact on mechanical performance. A novel approach to control the self-assembly behavior of hierarchically structured fibrous reinforcements is presented, achieved by tailoring the surface chemistry of the GFs to optimize the density of covalently bonded GnPs. Structure-property relationships were established by comparing the GnP bonding density on the GFs and degree of trans-crystallization as a function of amino-surface modification with the mechanical performance of the fabricated composites. Tailoring the microstructural architecture can significantly improve the mechanical properties of these hybrid composites, due to improved stress transfer at the interface. This improvement arises from the increased interfacial area of the hierarchically structured hybrid reinforcement, which facilitates trans-crystalline growth at the interface. Additionally, the remaining un-bonded GnPs facilitate β-crystal nucleation in the bulk, improving the composite’s toughness. The hybrid composite with the highest GnP bonding density and the greatest degree of trans-crystallization demonstrates exceptional mechanical performance. Specifically, this hybrid composite exhibits an impact strength of ~ 63% greater than that without hierarchical reinforcement, along with tensile strength and toughness improvements of ~ 40% and ~ 77%, respectively.

Polymer dielectrics with high energy density (ED) and excellent thermal resistance (TR) have attracted increasing attention with miniaturization and integration of electronic devices. However, most polymers are not adequate to meet these requirements due to their organic skeleton and low dielectric constant. Herein, we propose to fabricate ternary hybrid materials with improved ED and TR via self crosslinking of phthalonitriles terminated polyaryl ether nitrile (PEN), phthalonitriles modified boron nitride (BN-2CN), and carbon nanotube (CNT-2CN). FTIR, DSC, TGA, XPS, DMA, AFM, and SEM measurements confirm the fabrication of the CPEN-BN-CNT hybrids. With the addition of BN-2CN and CNT-2CN, the dielectric constant and breakdown strength of these hybrids are synergistically enhanced; as a result, the discharged ED of CPEN-BN8-CNT1 is increased to 2.48 J/cc, with an increment of 188% comparing with that of PEN. Accounting for the crosslinking of CPEN-BN-CNT hybrids, their TR is obviously promoted with their T_g and T_5% higher than 420 and 520 °C. Thermal decomposition kinetics calculations show that CPEN-BN8-CNT1 can be continuously used at 300 °C for 7.5 × 10⁴ years and 350 °C for 12.6 years. Therefore, the fabricated CPEN-BN-CNT hybrids demonstrate leaps in ED and TR simultaneously, which is an important reference for the preparation of advanced polymeric dielectrics.