Carbon Nanotube Composites Research Articles

Effect of carbon nanotubes and zinc oxide on electrical and mechanical properties of polyvinyl alcohol matrix composite by electrospinning method.

In this study, polymer composite nanofibers and thin membranes were synthesized using Carbon Nanotubes (CNTs) and Zinc Oxide (ZnO) as fillers in a Polyvinyl Alcohol (PVA) matrix, aiming to evaluate their electrical and mechanical properties. The composite nanofibers and thin membranes were prepared by incorporating different weight ratios of CNTs and ZnO into the PVA matrix using electrospinning and solution casting techniques, respectively. Solutions were prepared by mixing specific weight ratios of PVA, ZnO, and CNTs, followed by magnetic stirring and ultrasonication for homogenization. Electrospinning was performed at 20kV with a syringe-to-collector distance of 14.5cm at flow rate of 2.4ml/hr. The composites were characterized using FTIR spectroscopy and Scanning Electron Microscopy (SEM). The PVA/5%ZnO/0.5%CNT composite exhibited the highest dielectric constant of 10.3 at high frequencies, while PVA/5%CNT showed the highest capacitance of 31.1 pF at 2MHz. The maximum AC conductivity of 2.72 × 10- 7S/m was also observed for the PVA/5%ZnO/0.5%CNT composite. Mechanical testing revealed significant improvements in Young's modulus, stress yield, and load yield, with PVA/5%CNT achieving a Young's modulus of 387.12 MPa and a stress yield of 6.92 MPa. The addition of ZnO and CNT fillers resulted in enhanced electrical and mechanical properties, making these composites suitable for applications in microelectronic devices and packaging materials.

Construction of multi-functional silicone rubber/reduced graphene oxide/multi-walled carbon nanotube composites with segregated structure by surfactant-free Pickering emulsion method

Polymer composites with segregated structure (PC–S) have the advantages of low filler usage and excellent functionality. Emulsion blending combined with direct molding technology is the main method for the preparation of PC-S. However, due to the high fluidity of low-viscosity silicone rubber (SR), PC-S cannot be prepared by this technique. In addition, surfactants affect the heat resistance of the final SR composites (SRC). In order to solve the above problems, in this study, a Pickering emulsification combined with pre-crosslinking technology for SR was successfully developed by using graphene oxides (GO)/multi-walled carbon nanotubes (MWCNTs) hybrid fillers (GM) as emulsifiers, and SR/reduced GO (RGO)/MWCNTs composites with segregated structure (SSGM) were prepared. When RGO content is 4.5 wt%, MWCNTs content is 3.2 wt%, SSGM shows the highest electrical conductivity of 12.5 S/m, the highest electromagnetic interference shielding efficiency (EMI SE) of 41.4 dB, and an excellent flame retardant performance. The whole preparation process avoids the use of organic solvents and surfactants, which reduces the production cost of SSGM and the environmental pollution, and provides a feasible preparation route for the industrialized production of SSGM.

Synergistic chemical traction and pre-intercalation strategies enable high-quality MnO2 composites for efficient ammonium capture

The δ-MnO2 exhibits an ideal capacitive deionization (CDI) electrode for the efficient removal of ammonium ions (NH4+), owing to its unique layered structure that facilitates effective insertion and extraction of ions. However, MnO2 is constrained by self-aggregation, inadequate electrical conductivity, and sluggish reaction kinetics in practical applications, leading to subpar ammonium removal performance. Here, the polyaniline (PANI) intercalated MnO2 and carbon nanotubes (CNTs) composites (P/M-C-X) were synthesized by a straightforward and swift one-step inorganic/organic interface reaction using the chemical traction effect of aniline. The synergistic effect of the increased layer spacing and the introduced oxygen vacancy after PANI intercalated and the 1D/2D conductive interconnect structure constructed by CNTs can effectively improve the electrical conductivity, promote ions/electrons diffusion, and enhance the charge reaction kinetics. As results, P/M-C-50 exhibits excellent NH4+ removal performance, including the maximum salt adsorption capacity (SAC) (160.0 mg g−1), ultra-high salt adsorption rate (SAR) (1.07 mg g−1 s−1), and good cyclic stability. Furthermore, the comprehension of NH4+ storage mechanism has been enhanced through structural characterization, electrochemical analysis, and theoretical calculation. This study shows that P/M-C-50 has broad potential as a CDI ammonium removal electrode, and lays a solid foundation for the effective recovery and reuse of ammonium resources.

Understanding the Morphology and Cross‐Link Density in Silicone Rubber‐Multiwalled Carbon Nanotube Composites via Solvent Transport Studies

ABSTRACTThe diffusion characteristics of silicone rubber‐based nanocomposites have not been extensively studied in the literature. This study aims to provide a comprehensive analysis of the solvent transport properties of these materials, incorporating detailed dissolution modeling. This study reported a novel approach to elucidate the morphological and diffusion characteristics of silicone rubber‐MWCNT (multiwalled carbon nanotube) composites. FESEM micrograph analysis reveals structural changes with the lower loadings forming continuous networks and higher loadings leading to agglomeration of the fillers. Diffusion studies highlight reduced solvent uptake over time due to compact physical networks, while Kraus plot analysis confirms MWCNTs' reinforcing ability. Dissolution modeling using Korsmeyer–Peppas and Peppas–Sahlin models indicates the type of solvent release behavior, with the latter offering a superior fit. Mode of transport analysis suggests a less Fickian mode influenced by MWCNT loading, while swelling parameters demonstrate hindered solvent transport with increasing MWCNT content. The molecular mass between successive cross‐links and the cross‐link density decreases with rising MWCNT loading, which is theoretically predicted by the affine model. This study also focused on the complex interplay between filler loading, composite structure, and solvent transport behavior in silicone rubber‐MWCNTs composites, offering valuable insights for their potential applications in various fields.

Bionic Fluorine-Free Multifunctional Photothermal Surface for Anti/de/Driving-Icing and Droplet Manipulation.

Due to safety concerns associated with ice accumulation, there is a need to develop a durable surface with anti/de-icing properties. Inspired by Gecko skin and Nepenthes, a superhydrophobic photothermal surface (SH-PS) with micro-nano hierarchical structure based on carbon nanotube composites is prepared by one-step laser method. It can be switchable to a slippery photothermal surface (S-PS) by injecting silicone oil. S-PS can effectively delay icing at -20 °C/-30 °C, and maintain excellent dynamic anti-icing capabilities following 28 times supercooled droplet impact (-30 °C). Under near-infrared (NIR) irradiation, S-PS exhibits high-efficiency photothermal deicing and excellent ice droplet control capabilities. Furthermore, S-PS also exhibits remarkable droplet manipulation capabilities under NIR irradiation, even anti-gravity transport (8°) and programmable track manipulation. Notably, after 20m abrasion, the S-PS still maintains good performances of anti/de-icing and droplet manipulation after infusing lubricant. All these excellent performances can promote its application in a wider range of fields.

Heat Transfer in Carbon-Nanotube Dispersions: A Simulation Study of the Role of Nanotube Morphology and Connectivity

Simulation of the behavior of carbon nanotubes (CNTs) can become a very challenging task considering their complicated shape and large aspect ratio. This study aims to elucidate the role of CNT shape, length, and connectivity during heat transfer in CNT dispersions through a three-dimensional (3D) simulator. Three characteristic shapes for the CNTs are considered, namely, straight, moderately curved, and strongly curved. The results reveal that the commonly used assumption of viewing CNTs as straight cylinders leads to significant overestimation of the overall medium conductivity. The CNT length has an important effect on the nanofluid conductivity for all types of CNT shapes considered here. In addition, use of CNTs with higher conductivity than a certain value appears to have no further beneficial effect, thus relaxing the need for extremely pure or single-wall CNTs. On the contrary, the conductivity remains a strong function of the CNT concentration and may be even increased upon organization of CNTs into loose clusters. The overall approach and concept can be extended to CNT composites in a straightforward manner.

Highly stretchable carbon-based triboelectric nanogenerator textiles woven using coaxial fibres via direct ink writing

In recent years, triboelectric nanogenerators have seen great progress in the Internet of Things, wearable electronics, virtual reality and artificial intelligence technologies. However, current triboelectric nanogenerator devices generally face challenges of complex preparation processes and structures, hindering their application in large-area wearable textiles. In this study, we develop highly stretchable triboelectric fibres using direct ink writing as building blocks for further woven textiles. This consists of a conductive core and insulating sheath, namely composites of multi-wall carbon nanotube and fluorinated ethylene propylene particles, both doped in silicone rubber. The fibre enjoys outstanding electrical performance, as well as excellent mechanical stretchability. Particularly, a single-centimetre-long fibre, upon slight patting, can surprisingly produce an open-circuit voltage of 8 V, a short-circuit current of 110 nA and 2.5 nC short-circuit transferred charges, or equivalent lighting of four to five commercial light-emitting diodes alone, greatly outperforming current wearable devices. These fibres also can endure an extraordinary strain of up to ∼874 %. The fibres are then woven into wearable gloves and socks using traditional weaving techniques, which can realise motion pattern identification and recognition with classification accuracy as high as ∼96 % using convolutional neural networks. This creates application prospects in wearable electronics, providing a scalable and affordable method for weaving daily wearable textiles and favouring large-area, wearable, self-powered sensors and artificial intelligence technologies.

Preparation of a V–COF@SWCNTs-COOH/SPCE supported molecularly imprinted electrochemical sensor for real-time detection of trace sulfadimidine

To overcome the limitations of insufficient sensitivity and poor specificity of portable screen-printed carbon electrode-electrochemical sensors (SPCE-EC) in practical applications, we prepared carrier composites of carboxylic single-walled carbon nanotubes vertically grafted by covalent organic frameworks (v-COF@SWCNTs-COOH) and coated with a molecularly imprinted polymer (MIP) of sulfadimidine (SM2). 55 °C hot steam elution is more eco-friendly than traditional organic solvent elution. The results showed that when the mass ratio of DBA to DBA-SWCNTs was 1:1, the v-COF@SWCNTs-COOH obtained by the two-step synthesis method could increase the electrical signal up to 2.33-fold of the bare electrode. The bifunctional monomer MIP prepared on the above structure enhanced the signal response by 2.91-fold, with a high imprint factor of 20. The assembled MIP/v-COF@SWCNTs-COOH/SPCE were analyzed by differential pulse voltammetry (DPV) with a high sensitivity of 0.21 nM for LOD and 0.70 nM for LOQ. In milk and fish samples, the recovery rate was 95.0 %–104.8 %. The validation of authentic pork samples with the statutory LC-MS/MS method showed no significant difference (P > 0.05). The sensor's performance indicators remained robust after five repeated uses. Therefore, the MIP/v-COF@SWCNTs-COOH/SPCE combines the cheapness and portability of SPCE, while the sensitivity and specificity of small molecule detection were significantly improved.

Multifunctional tri-electrode sensors for the measurement of displacement, force, and infrared irradiation

Abstract Here we described the effect of displacement, force and infrared irradiation on the resistance and impedance of tri-electrode multifunctional sensors. These sensors are based on the gel type composite of carbon nanotubes (CNT), nickel phthalocyanine (NiPc) and edible oil. The channel of this tri-electrodes (field effect transistors) structure is made of CNT-NiPc-oil gel composite using rubbing-in technology. The tri-electrode sensors’ response depends upon the direction of force/displacement and shows an anisotropy. Application of force or displacement from the top causes to decrease resistance and the impedance and vice versa in case of applying force or displacement from the side. The displacement and force sensitivities were up to -273.3 Ω/µm and -46.5 Ω/gf from the top and 480.0 Ω/µm and 3.1 x 102 Ω/gf from the side, respectively, for the sensing ranges 0-150 µm and 0-215 gf. Under the effect of the infrared irradiation from any direction the impedance and the resistance of the sensor reduces. On changing infrared irradiation intensity from 0 to 2500 W/m2 the sensitivities from top and side of the sensor were -37.4 Ωm2/W and -16.5 Ωm2/W, respectively. The investigated sensors may potentially be used as prototypes to develop gel-electronic-based shockproof sensors. The technological achievement in fabricating these devices is the consumption of environmentally friendly materials, particularly edible oil (organic). The edible oil allows to formulate uniform composite gel-films, that may not be comprehended only by ingredients mixing. The fabricated sensors are highly attractive for commercialization.

Cobalt vanadate intertwined in carboxylated multiple-walled carbon nanotubes for simultaneous electrochemical detection of ascorbic acid, dopamine and uric acid

Low-cost transition metal vanadate-based electrochemical sensors have attracted a lot of attention recently. A cobalt vanadate and carboxylated multi-walled carbon nanotube composite (CoV/MWCNTs-COOH) was prepared by an ultrasonic-assisted assembly method. The uniform and dense MWCNTs-COOH attached to the surface of CoV not only combines the large surface area and superior conductivity of MWCNTs-COOH with the excellent electrochemical activity of CoV, but also enhances the redox reaction between CoV/MWCNTs-COOH composite and the analyte through synergistic effect of hydrogen bonding and electrostatic interaction. The electrochemical behaviors of CoV/MWCNTs-COOH composite modified glassy carbon electrode (CoV/MWCNTs-COOH/GCE) were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The simultaneous electrochemical sensing of ascorbic acid (AA), dopamine (DA) and uric acid (UA) on CoV/MWCNTs-COOH/GCE possesses good peak current signals with well-defined peak potentials. The linear ranges of AA, DA, and UA at CoV/MWCNTs-COOH/GCE are 1.0–100.0 μM, and the limits of detection (LODs; S/N = 3) are 0.4 μM, 0.03 μM, and 0.1 μM, respectively. The practicality of the designed sensor was further confirmed by the good recoveries obtained in the simultaneous measurement of actual samples including fetal bovine serum, human serum, urine, and Vitamin C tablets. Overall, the developed electrochemical sensor shows potential therapeutic applications for simultaneous determination of AA, DA and UA in biological fluids.

Effects of carbon nanotubes on the isotropic to nematic phase transition in nematic liquid crystal elastomer

The isotropic to nematic phase transition on nematic liquid crystal elastomer - carbon nanotubes composites has been studied theoretically. The model free energy density has been constructed using Flory Huggins theory of isotropic mixing and Landau-de Gennes theory. The effects of carbon nanotubes and external mechanical stress on the isotropic to nematic phase transition of the nematic liquid crystal elastomer-carbon nanotubes composites have been discussed. The volume fraction of carbon nanotubes dependence of the isotropic to nematic transition temperature, mechanical strain and strain birefringence has been calculated. The weak first-order character of the isotropic to nematic phase transition on nematic liquid crystal elastomer-carbon nanotubes composites has been predicted.

Flexible beads-on-string hierarchically porous carbon nanofiber/nanotube composites for enhanced capacitive deionization performance in water desalination

Capacitive deionization (CDI) has garnered significant interest for desalinating water and wastewater. However, electrode materials have remained a primary constraint in CDI technology. This study incorporated carbon nanotubes (CNTs) into a polyacrylonitrile (PAN) solution to synthesize a hierarchically porous activated carbon nanofiber (ACNF)/CNT composite. The ACNF/CNT composite possesses a highly flexible structure characterized by a distinctive beads-on-string morphology. It exhibits a specific surface area of 699 m2/g, a specific pore volume of 0.448 cm3/g, and an average pore width of 3.38 nm. The composite is composed of micropores (38 %), mesopores (59 %), and macropores, creating a multi-scale porous architecture. The surface capacitance of the ACNF/CNT composite is six times greater than that of the ACNF alone, and its charge transfer resistance is reduced to one-tenth. Furthermore, the electrosorption capacity of the ACNF/CNT composite as CDI electrodes was found to be 17.3 mg/g for a 500 mg/L NaCl solution, demonstrating stability over 30 cycles. Kinetic studies suggest that the mesopore-rich beads-on-string structure enhances intraparticle diffusion and the electrosorption process. The ACNF/CNT composite also demonstrates exceptional flexibility and mechanical stability, which are crucial for its application at a pilot scale. This study introduces a novel hierarchically porous electrode material for CDI desalination.

Hydrothermal synthesis and characterization of samarium molybdate nanosheets modified multi-walled carbon nanotubes: real-time analysis of dimetridazole in environmental and biological samples

Dimetridazole (DMZ) is commonly used as a veterinary drug, resulting in high emissions and environmental pollution and DMZ residues are carcinogenic, genotoxic, and mutagenic to humans. Therefore, it is essential to construct a fast, sensitive and simple sensor to monitor DMZ. In this study, samarium molybdate nanosheets modified multi-walled carbon nanotube composites (SmM/MWCNT) were synthesized to modify GCE for detecting DMZ. The SmM/MWCNT material was also characterized by various analytical and spectroscopic techniques, such as FE-SEM, HRTEM, FT-IR, Raman spectroscopy, XRD, elemental mapping and XPS, to demonstrate the successful synthesis of the composite. Besides, the electrochemical behavior of SmM/MWCNT /GCE for DMZ was also investigated using CV and DPV, and the modified electrode showed good electrochemical sensing performance for DMZ with a low detection limit (0.08 μM), a wide linear range (0.1∼1000 μM), and excellent selectivity. Finally, the SmM/MWCNT/GCE was successfully applied to detect DMZ in environmental and biological samples, and satisfactory recoveries (95%∼105%) were obtained. To the best of our knowledge, the synthesis of SmM/MWCNT and its application in electrochemical sensors are reported for the first time, which demonstrates that it can provide a new route for real-time monitoring of environmental pollutants.

Improved thermoelectric properties of metal ion doped aniline tetramer/carbon nanotube composite films

Carbon nanotubes and their composites have attracted much attention in the field of thermoelectric conversion for potential application in wearable electronics owing to their good electrical conductivity and excellent mechanical properties. However, low Seebeck coefficient of carbon nanotubes limit the improvement of their thermoelectric properties. In this work, metal ions (Mn+ = Fe3+, Ni2+, Cu2+) are used to further improve the thermoelectric properties of aniline tetramer (ANIT)/single-walled carbon nanotubes (SWCNT) composites, and Mn+@ANIT/SWCNT films are prepared by physical mixing and vacuum filtration method. The metal ions and concentrations for improving Mn+@ANIT/SWCNT thermoelectric films are optimized, and the metal ions doping optimizes carrier concentration and promotes carrier transport of the composites appropriately, which increased the Seebeck coefficient. Amone the prepared Mn+@ANIT/SWCNT films, the Cu2+@ANIT/SWCNT demonstrates the highest PF value of 145.3 ± 3.9 μW m−1 K−2 at the molar ratio of Cu2+/ANIT to being 5:100 with the σ of 560.1 ± 22.1 S cm−1, and the S of 51.0 ± 1.3 μV K−1 at room temperature. Finally, five pairs of p-type Cu2+@ANIT/SWCNT films and n-type copper sheets are connected in series to assemble a self-powered thermoelectric device, which demonstrates an actual output power of about 426 nW under a temperature difference of 50 K. Therefore, this work offers a metal ions doping strategy to improve the SWCNT composites with enhanced thermoelectric properties.

Extremely durable electrical impedance tomography–based soft and ultrathin wearable e-skin for three-dimensional tactile interfaces

In the rapidly evolving field of human-machine interfaces (HMIs), high-resolution wearable electronic skin (e-skin) is essential for user interaction. However, traditional array-structured tactile interfaces require increased number of interconnects, while soft material–based computational methods have limited functionalities. Here, we introduce a thin and soft e-skin for tactile interfaces, offering high mapping capabilities through electrical impedance tomography (EIT). We employed an organic/inorganic hybrid structure with simple, cost-effective fabrication processes, ensuring flexibility and stability. The conductive and stretchable sensing domain includes a micropatterned multiwall carbon nanotube and elastomer composite. The skin-like tactile interface effectively detects pressure-induced conductivity changes, offering superior spatiotemporal resolution with fewer interconnects (pixel/interconnects >57). This EIT-based tactile interface discerns external pressures to a submillimeter degree and vertical deformations of a few hundred micrometers. It sustains stable functions under external damage or environmental changes, confirming its suitability for persistent wearable use. We demonstrate practical applications in real-time HMIs: handwriting recognition and drone control.

Adsorption and catalytic degradation of Light green SF by magnetic PEI-modified carbon nanotubes composites

Treatment of colored effluent is necessary for the textile industry. In this study, a magnetically recyclable composite (MnFe2O4@cCNTs-PEI) was prepared by coprecipitation and grafting methods, and its efficiency for removal of light green SF (LG) from solution assessed via the adsorption and advanced oxidation techniques. The experimental results indicated that the maximum adsorption capacity of MnFe2O4@cCNTs-PEI towards LG could reach 371 mg‧g−1 at solution pH 3 and 303 K. The adsorption equilibrium results could be well fitted by Koble-Corrigan, Temkin, and Freundlich isotherm models whereas the adsorption kinetic process follows the Elovich equation and Double Constant model. This implies the adsorption process be heterogeneous multimolecular layer adsorption, accompanied by heterogeneous diffusion. The adsorption process was spontaneous, endothermic and entropy increasing which was majorly controlled by the electrostatic attraction and π-π stacking mechanisms. MnFe2O4@cCNTs-PEI can catalyze and activate H2O2 to achieve a heterogeneous Fenton-like degradation of LG. MnFe2O4@cCNTs-PEI as a catalyst could achieve a higher removal rate of LG (90 %) within a broad pH range (3–10) which could be ascribed to the presence of active radical species such as ‧OH and 1O2. After three adsorption and degradation regeneration cycles, the removal rate of LG was still higher than 60 %. It is potential for MnFe2O4@cCNTs-PEI to be economically viable for practical applications.

Fabrication of boron nitride/copper oxide@multi-walled carbon nanotubes composites for enhancing heat transfer and photothermal conversion of phase change materials

To realize the efficient storage and conversion of solar energy by phase change materials (PCMs), low photothermal conversion efficiency and poor heat transfer performance remain great challenges. Herein, polyethylene glycol (PEG)-based composite PCMs with excellent photothermal conversion performance and exceptional thermal management capability were obtained by using boron nitride/copper oxide@multi-walled carbon nanotubes (BN/CuO@MWCNTs) as the thermal conductive and photothermal conversion enhancement fillers. The results indicate that owing to the bridging effect, the introduction of CuO and MWCNTs on the BN surface can construct additional heat transfer paths, resulting in a high thermal conductivity of up to 2.35 W/(m·K) for the as-prepared PEG/BN/CuO@MWCNTs composite, which is about 9-folds enhancement than pristine PEG. Simultaneously, the supercooling degree of PEG in PEG/BN/CuO@MWCNTs is effectively suppressed due to the synergistic nucleation effect of BN, CuO and MWCNTs. Additionally, the PEG/BN/CuO@MWCNTs composites not only exhibit a high latent-heat capacity of 154.5 J/g and a high photothermal conversion efficiency of 92.2 %, but also show favorable shape stability and durable reliability. This work offers a workable solution for the synergistic enhancement of photothermal conversion and thermal management, which can effectively promote the practical application in solar energy conversion and storage.

Carbonaceous Shape-Stabilized Octadecane/Multi-Walled Carbon Nanotube Composite Materials for Enhanced Energy Storage and Electromagnetic Interference Shielding.

Developing materials for efficient energy storage and effective electromagnetic interference (EMI) shielding is crucial in modern technology. This study explores the synthesis and characterization of carbonaceous shape-stabilized octadecane/MWCNT (multi-walled carbon nanotube) composites, utilizing activated carbon, expanded graphite or ceramic carbon foam, as shape stabilizers for phase change materials (PCMs) to enhance thermal energy storage and EMI shielding, for energy-efficient and advanced applications. The integration of octadecane, a phase change material (PCM) with carbonaceous stabilizers ensures the material's stability during phase transitions, while MWCNTs contribute to improved thermal storage properties and EMI shielding capabilities. The research aims to develop novel composites with dual functionality for thermal storage and EMI shielding, emphasizing the role of carbon matrices and their MWCNT composites. SEM and CT microtomography analyses reveal variations in MWCNT incorporation across the matrices, influenced by surface properties and porosity. Leaching tests, infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) confirm the composite's stability and high latent heat storage. The presence of nanotubes enhances the thermal properties of octadecane and ΔH values almost reached their theoretical values. EMI shielding effectiveness measurements indicate that the composites show improved electric properties in the presence of MWCNTs.

Enhancing the Fenton catalytic activity of Fe-MOFs by incorporation of carbon nanotubes: The crucial role of C-O-Fe coordination structure

Fe-based metal–organic frameworks (MOFs) have garnered significant attention as catalysts for heterogeneous Fenton reactions, while the limited efficiency of the Fe(III)/Fe(II) redox cycle hinders their widespread use in wastewater treatment. Herein, we successfully incorporated carbon nanotubes (CNTs) into MIL-101(Fe) to modulate the coordination environment of Fe for achieving better catalytic activity. The MIL-101(Fe)/CNTs/H2O2 system shows outstanding performance in degrading various pollutants, with the catalytic activity of the MIL-101(Fe)/CNTs composites (98.8%) significantly surpassing that of MIL-101(Fe) alone (26.4%) or CNTs alone (3.5%). Multiple experimental findings suggest that this synergistic effect is primarily attributed to the C-O-Fe bridge bonds resulting from the interaction of surface carboxyl groups on CNTs with Fe in MIL-101(Fe). This unique coordination structure accelerates the redox cycle of Fe(III)/Fe(II), thereby promoting the generation of hydroxyl radicals (HO•). Furthermore, the MIL-101(Fe)/CNTs composites demonstrate excellent reusability and stability, maintaining effectiveness over a wide pH range from 3.0 to 6.5. This study provides new insights into regulating the microstructure of Fe-based MOFs to enhance their Fenton catalytic activity.

Properties of polyphenylene sulfide/multiwalled carbon nanotubes composites: a comparison between compression molding and microinjection molding

Abstract This work comparatively studied the electrical, morphological, and thermal properties of polyphenylene sulfide/multiwalled carbon nanotubes (PPS/CNT) composites which were prepared by compression molding (CM) and microinjection molding (μIM), respectively. The subsequent samples were termed as CM composites and microparts, respectively. Results revealed that the electrical conductivity of PPS/CNT microparts was lower than that of CM PPS/CNT composites, which was ascribed to the difference in shearing influence that affected microstructural evolution in resultant moldings. In addition, SEM observations revealed that the distribution of CNTs became better in the PPS/CNT microparts, which was related to the prevailing higher shearing effect in μIM. The tensile strength of PPS/CNT microparts dropped for filler concentrations ≤2 wt% and it started to increase after that reached 10 wt%; in comparison with the PPS/CNT microparts, the tensile strength of CM PPS/CNT samples exhibited an opposite trend when the filler concentration was ≤3 wt%. After that, the tensile strength of CM samples showed a monotonic increase with increasing CNT concentrations. Both the uniform distribution of CNT and increase of crystallinity were crucial to improving the tensile strength of PPS/CNT moldings. This work showed that PPS/CNT moldings with good electrical conductivity and mechanical performance can be molded at relatively high filler concentrations, which is critical for applications in demanding engineering sectors.