Modified Carbon Nanotubes Research Articles

Bonding and fracture properties of SPI-CNTs/epoxy adhesive on SPI-CNTs deposited CFRP composites

Adhesive bonding is frequently used to connect CFRP structures due to its lightweight, easy implementation and high production efficiency. However, the bonding performance of adhesive is far from satisfactory as dimension and complexity of CFRP structures increase. In this paper, a new bonding strategy for CFRP structures via introducing soy protein isolate modified carbon nanotubes (SPI-CNTs) both in the epoxy resin adhesive and on the bonding parts' surface is proposed. Results showed that SPI can effectively improve CNTs' dispersion on the two areas, notably enhancing the bonding performance of the adhesive. When 0.3 wt% SPI-CNTs was added in the adhesive, its adhesive shear strength increased to 12.76 MPa, which was 72 % higher than the unmodified CNTs/epoxy adhesive. Based on this concentration, the SPI-CNTs was deposited uniformly on the surface of the CFRP adherends via bath sonication and resulted in a maximum shear strength of 15.59 MPa, which was 22.2 % greater than the untreated ones. Based on the above condition, the Mode I fracture toughness G1c and the Mixed-Mode I/II fracture toughness Gc could reach a maximum of 0.31 and 0.44 N/mm respectively, which were 117 % and 97 % higher than the pure epoxy adhesive. The present work shows a new pathway for the effective bonding of CFRP structural components used in the aerospace industry.

Solid-State Microfabricated Potentiometric Sensors for Selective Assessment of Diclofenac Sodium Utilizing Pentafluorophenyl Diazonium Modified Carbon Nanotubes Transducer Layer

In the pharmaceutical field, analytical chemistry is evolving and one area that is experiencing enthusiasm is the design and implementation of solid contact ion-selective electrodes. We have developed two potentiometric sensors for the selective assay of a widely used drug diclofenac sodium. Diclofenac sodium was targeted in one of its most recommended dosage forms (Arthrotec® tablets) in the presence of misoprostol. A cost-effective copper printed circuit board as a substrate has been coated with a PVC sensing membrane to fabricate sensor I. Hydrophobic carbon nanotubes (CNTs) have been modified through in situ reduction of pentafluorophenyl diazonium using sodium borohydride. An interlayer of the modified CNTs was inserted as a transducer layer between the Cu substrate and the ion-sensing membrane in sensor II to enhance its electrochemical performance and stability. The microfabricated electrodes demonstrated encouraging outcomes upon the direct assay of diclofenac sodium in combination with misoprostol and other additives without sample preparation steps. The responses presented a linear Nernstian pattern in the range of 1.0 × 10−4 to 1.0 × 10−2 mol l−1 with a slope of −58.2 and −58.4 mV/decade for sensors I and II, consequently. Finally, the sustainability of the developed technique was assured using advanced green metrics.

Influence of the Oxidized Carbon Nanotubes Modification Conditions on Their Catalytic Activity and Selectivity in the Oxygen Reduction Reaction to Hydrogen Peroxide

Influence of the Oxidized Carbon Nanotubes Modification Conditions on Their Catalytic Activity and Selectivity in the Oxygen Reduction Reaction to Hydrogen Peroxide

Novel CNT/MXene composite membranes with superior electrocatalytic efficiency and durability for sustainable wastewater treatment

Self-assembled composite membranes are increasingly acknowledged for their potential in wastewater treatment due to their superior selectivity, high operational efficiency, and environmental sustainability. Nonetheless, challenges such as inadequate removal efficiencies for low molecular weight dyes and significant membrane fouling restrict their broader industrial application. To address these challenges, a structurally stable composite membrane of sodium lignosulfonate carbon nanotubes/alkalized MXene (SLS-CNT/alk-MXene) has been engineered. This membrane employs a polyethersulfone substrate pretreated with dopamine for uniform nanoparticle assembly through a layer-by-layer self-assembly technique. The manufacturing process includes hydrophilic modification of carbon nanotubes with lignosulfonate, followed by alkalization of MXene using sodium hydroxide. Performance evaluation of the M2 composite membrane, with a content ratio of SLS-CNT to alk-MXene of 4:2 by weight, revealed outstanding membrane properties. It achieved high selective permeability, with over 99 % retention efficiency for Methyl Blue and Congo Red, and a permeation flux of 51.6 L m-2h−1 bar−1. This membrane efficiently degraded various organic dyes within 1h, including Methyl Orange, Methylene Blue, Malachite Green, and Rhodamine B, and thanks to the integration of electrocatalysis with membrane separation, while maintaining a low membrane resistance of only 813 Ω. After environmentally sustainable testing, the membrane displayed excellent stability and 80 % recovery capacity, presenting a novel approach and design blueprint for enhancing clean water resources and environmental protection.

Integrated biosensor array for multiplex biomarkers cancer diagnosis via in-situ self-assembly carbon nanotubes with an ordered inverse-opal structure

To enhance the precision and reliability of early disease detection, especially in malignancies, an exhaustive investigation of multi-target biomarkers is essential. In this study, an advanced integrated electrochemical biosensor array that demonstrates exceptional performance was constructed. This biosensor was developed through a controllable porous-size mechanism and in-situ modification of carbon nanotubes (CNTs) to quantify multiplex biomarkers—specifically, C-reaction protein (CRP), carbohydrate antigen 125 (CA125), and carcinoembryonic antigen (CEA)—in human serum plasma. The fabrication process involved creating a highly ordered three-dimensional inverse-opal structure with the CNTs (pCNTs) modifier through microdroplet-based microfluidics, confined spatial self-assembly of nanoparticles, and chemical wet-etching. This innovative approach allowed for direct in-situ modification of nanomaterial onto the surface of electrode array, eliminating secondary transfer and providing exceptional control over structure and stability. The outstanding electrochemical performance was achieved through the synergistic effect of the pCNTs nanomaterial, aptamer, and horseradish peroxidase-labeled (HRP-) antibody. Additionally, the integrated biosensor array platform comprised multiple individually addressable electrode units (n = 11), enabling simultaneous multi-parallel/target testing, thereby ensuring accuracy and high throughput. Crucially, this integrated biosensor array accurately quantified multiplex biomarkers in human serum, yielding results comparable to commercial methods. This integrated technology holds promise for point-of-care testing (POCT) in early disease diagnosis and biological analysis.

Application of Poly Dl‐Phenylalanine Modified Carbon Nanotube Electrode for Sensitive and Selective Detection of Tinidazole

AbstractThe present study aimed to design an electrochemical sensor for the detection of tinidazole (TN) by carbon nanotube electrode (CNTE) modified with dl‐phenylalanine (DL‐PA). The unmodified carbon nanotube electrode (UMCNTE) and poly (DL‐PA) modified carbon nanotube electrode (P(DL‐PA) MCNTE) were characterized by Scanning emission microscopy (SEM) images. Electrochemical techniques like cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV), were implemented to evaluate the efficiency of the developed electrode toward the detection of TN. The impact of pH on the modified electrode showed that the P(DL‐PA) MCNTE gave a good voltammetric response at pH 3.5. The effect of accumulation time, scan rate, and variation of concentration of TN at the surface of the developed sensor was analyzed. The scan rate study showed that the reduction reaction of TN involves a two‐electron transfer process and it is adsorption‐controlled. The detection limit studies for CV and DPV gave good linearity in the linear range 0.6 μM to 100.0 μM and 3.0 μM to 100.0 μM respectively. The limit of quantification (LOQ) and limit of detection (LOD) concerning CV were found to be 0.65 μM and 0.19 μM respectively. The LOQ and LOD for DPV were calculated to be 0.33 μM and 0.10 μM respectively. The P(DL‐PA) MCNTE showed good anti‐interferent properties. The developed sensor has good stability, repeatability, and reproducibility for the analysis of TN. The P(DL‐PA) MCNTE was successfully employed in the real sample analysis.

Enhancement of mechanical and flame‐retardant properties of PLA composites through the combined action of flexible chain segments and hydrogen bonding interactions

AbstractThe development of high toughness as well as flame‐retardant polylactic acid (PLA) materials is important for expanding the practical applications. Herein, a type of high toughness PLA composites with improved flame retardancy was developed through combining modified carbon nanotubes (CNT) and polysiliconoxaborane (PBSi) with PLA matrix. The optimal PLA composite (PLA/PBSi/CNT‐3.0) exhibited excellent crystallization degree (18.7%), thermal stability (the Ea significantly increased), flame retardancy (the values of peak heat release rate (PHRR) polarized optical microscopy and total heat release (THR) decreased to 287.1 W/g and 15.5 kJ/m2, respectively), and mechanical properties (the elongation at break increased to 149.5%, with an increasement of 1745.7%) due to the combined action of flexible chain segments and hydrogen bonding interactions. Furthermore, the toughening mechanism of the PLA/PBSi/CNT composites was illustrated and attributed to the combination of flexible SiOBO segments and two dominant energy dissipation processes (the breakage of hydrogen bond and the destruction of microcrystals). Overall, this work provided a facile approach for improving the toughness and flame retardancy of PLA, which was conducive to expanding the application range of PLA.

A fluorine-free and high-robustness photothermal self-healing superhydrophobic coating with long-term anticorrosion and antibacterial performances

Superhydrophobic surface is a promising strategy for antibacterial and corrosion protection. However, the use of harmful fluorine-containing materials, poor mechano-chemical stability, the addition of fungicides and poor corrosion resistance often limit its practical application. In this paper, a high-robustness photothermal self-healing superhydrophobic coating is prepared by simply spraying a mixture of hydrophobically modified epoxy resin and two kinds of modified nanofillers (carbon nanotubes and SiO2) for long-term anticorrosion and antibacterial applications. Multi-scale network and lubrication structures formed by cross-linking of modified carbon nanotubes and repeatable roughness endow coating with high robustness, so that the coating maintains superhydrophobicity even after 100 Taber abrasion cycles, 20 m sandpaper abrasion and 100 tape peeling cycles. The synergistic effect of antibacterial adhesion and photothermal bactericidal activity endows coating with excellent antibacterial efficiency, which against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) separately reaches 99.6% and 99.8%. Moreover, the influence of modified epoxy resin, superhydrophobicity, organic coating and coating thicknesses on the anticorrosion of magnesium (Mg) alloy is systematically studied and analyzed. More importantly, the prepared coating still exhibits excellent self-cleaning, anticorrosion and antibacterial abilities after 20 m abrasion. Furthermore, the coating exhibits excellent adhesion (level 4B), chemical stability, UV radiation resistance, high-low temperature alternation resistance, stable heat production capacity and photothermal self-healing ability. All these excellent performances can promote its application in a wider range of fields.

Research Progress on the Removal of Heavy Metals in Water and Soil by Modified Carbon Nanotubes: a Review

Research Progress on the Removal of Heavy Metals in Water and Soil by Modified Carbon Nanotubes: a Review

Adsorption and separation of lead ions in phosphoric acid by co-doped carbon nanotubes with sulfur, oxygen, and manganese

The purpose of this study was to prepare a novel and efficient adsorbent for the removal of trace Pb(II) from phosphoric acid. Manganese oxide/sulfur-oxygen doped carbon nanotube composites (CNTs-S-O-Mn) were prepared from multi-walled carbon nanotubes modified with nitric acid, mercaptoacetic acid, acetic anhydride, concentrated sulfuric acid and potassium permanganate. Characterisation revealed that CNTs-S-O-Mn contained hydroxyl, sulphonate groups, MnO and Mn3O4. At 298 K, 15.362 mg·L-1 initial concentration of lead ions, and 18.4 % phosphoric acid concentration, the adsorption capacity of the composites for lead ions was 38.65 mg·g−1, which was higher than that of the unmodified CNTs, 8.04 mg·g−1. The adsorption kinetic data at 298 K conformed to the quasi-second-order kinetic equation, R2 = 0.997; 298, adsorption isotherms at 308 and 318 K conformed to the Langmuir equation, R2 = 0.990–––0.991. The adsorption capacity increased with decreasing phosphoric acid concentration. In this system, the adsorption is affected by a certain concentration of lead ions. Adsorption occurs via chemisorption and is exothermic. Sulfonic acid groups and hydroxyl groups on manganese oxides play an important role in the adsorption of Pb (II) through surface complexation with Pb (II). These results indicate that the removal of trace Pb (II) from phosphoric acid by modified carbon nanotubes is feasible, revealing a new use of carbon nanotubes for phosphoric acid purification.

Improvement of thermal, mechanical, and electromagnetic interference shielding properties of polyethylene nanocomposites by introducing non‐covalently modified carbon nanotube and reactive polyethylene copolymer

AbstractWe herein report the enhancement of thermal, electrical, electromagnetic interference (EMI) shielding, and mechanical performance of polyethylene (PE) nanocomposites by the introduction of non‐covalently modified multi‐walled carbon nanotube (MWCNT) and ethylene‐glycidyl methacrylate (EGMA) copolymer. For this purpose, benzylacetic acid‐functionalized MWCNT (BA‐M) is prepared by ball milling, and it is melt‐mixed with EGMA to prepare a masterbatch. The masterbatch is then melt‐compounded with neat PE to manufacture a series of PE/EGMA/BA‐M nanocomposites with 0.5–5 wt% MWCNTs. Electron microscopic and spectroscopic analyses confirm the successful fabrication of non‐covalently functionalized BA‐M, the uniform dispersity of MWCNTs in the PE matrix, and the chemical reactions between the carboxylic acid groups of BA‐M and the epoxy group of EGMA in the nanocomposites. Scanning calorimetric data reveals that BA‐M acts as an efficient nucleating agent for the crystallization of PE. The excellent dispersity and robust interfacial bonding of BA‐M in the PE matrix result in improved electrical and EMI shielding properties in PE/EGMA/BA‐M nanocomposites. Furthermore, the tensile strength, initial modulus, and impact strength of the nanocomposites gradually rise as the BA‐M content increases. Thus, the PE/EGMA/BA‐M nanocomposite containing 5 wt% MWCNT achieves excellent performance of EMI shielding effectiveness of ~14.7 dB/mm, tensile strength of ~34.5 MPa, initial modulus of ~295.7 MPa, and impact strength of ~539.9 J/m, which represent enhancements of ~265%, ~40%, ~82%, and ~452%, respectively, compared to pristine PE.Highlights Non‐covalently modified MWCNT (BA‐M) was prepared by facile ball milling. PE nanocomposites with BA‐M and EGMA were prepared by masterbatch melt‐mixing. Excellent dispersity and interfacial bonding of MWCNT in the PE matrix were attained. Tensile strength and initial modulus of the nanocomposites were highly improved. EMI shielding effectiveness of the nanocomposite with 5 wt% MWCNT was ~14.7 dB/mm.

Ab initio exploration of modified carbon nanotubes as potential corrosion inhibitors

In order to develop novel unexplored potential corrosion inhibitors, covalently modified single-walled carbon nanotubes (SWCNT) via benzoic (–PhCOOH) and aniline (–PhNH2) groups are being investigated as corrosion inhibitors for the first time. Utilizing a comprehensive approach, this study employed density functional theory (DFT), Monte Carlo (MC), and molecular dynamics simulations (MD) to assess the adsorption behavior of modified nanotubes as corrosion inhibitors on the Cu(111) surface within a simulated aqueous HCl corrosion medium. The results provided molecular information on the adsorption capability, geometry adsorption centers, and adsorption energies (Eads) of carbon nanotubes on the surface of Cu(111). The adsorption energy values unveiled robust interactions between SWCNT–PhCOOH and SWCNT–PhNH2 inhibitors and the Cu(111) surface, suggesting a highly effective corrosion protection mechanism. The calculated Eads values exhibited notable ranges, spanning from –260.82 to –308.18 kcal/mol for SWCNT–PhCOOH and –220.92 to –261.01 kcal/mol for SWCNT–PhNH2 with the maximum probability values, representing the most favorable adsorption scenarios, determined to be –292.96 and –229.39 kcal/mol, respectively. A key insight from Monte Carlo simulations underscored the inherent spontaneity of the adsorption process, corroborated by the consistently negative Eads values. These findings collectively underscore the substantial affinity of the inhibitors to the copper surface, contributing to a deeper comprehension of their corrosion inhibition capabilities.

A Composite Superhydrophobic, Photothermal Coating by Modified Carbon Nanotubes and the Study of Its Anti‐Icing/Deicing Behavior

Linearly structured carbon nanotubes (CNTs) are intertwined to form complex micro‐ and nanoscale structural undulations, and the structural undulations of the coating are further enhanced using large‐size nano‐SiO2. It can be prepared by the composite superhydrophobic coating (S‐C coating) with contact angle of 165.3° and sliding angle of 1°. Small‐size nano‐SiO2 can doped into the 3D‐network structure formed by the CNTs and act as anchor points to fix the structure. This enhances the stability of the coating as well as the abrasion resistance. The coating exhibits good long‐term durability and the ability to face harsh service environments. Due to the presence of the air layer with low heat transfer rate on the coating surface, the S‐C coating demonstrates good anti‐icing properties compared to the uncoated tinplate. By the lower surface free energy and contact area with the ice layer of the coating, the coating also exhibits good deicing performance. The ice adhesion strength of the coating is only 11.5 kPa. The photothermal properties of CNTs and the ability of the micro‐ and nanostructure to reflect light enable the coating to exhibit excellent photothermal properties. This also accelerates the melting and shedding of the ice layer on the coating.

Implanted Carbon Nanotubes Harvest Electrical Energy from Heartbeat for Medical Implants.

Reliability of power supply for current implantable electronic devices is a critical issue for longevity and for reducing the risk of device failure. Energy harvesting is an emerging technology, representing a strategy for establishing autonomous power supply by utilizing biomechanical movements in human body. Here, a novel "Twistron energy cell harvester" (TECH), consisting of coiled carbon nanotube yarn that converts mechanical energy of the beating heart into electrical energy, is presented. The performance of TECH is evaluated in an in vitro artificial heartbeat system which simulates the deformation pattern of the cardiac surface, reaching a maximum peak power of 1.42W kg-1 and average power of 0.39W kg-1 at 60 beats per minute. In vivo implantation of TECH onto the left ventricular surface in a porcine model continuously generates electrical energy from cardiac contraction. The generated electrical energy is used for direct pacing of the heart as documented by extensive electrophysiology mapping. Implanted modified carbon nanotubes are applicable as a source for harvesting biomechanical energy from cardiac motion for power supply or cardiac pacing.

Ruthenium nanoparticles supported on functionalized carbon nanotubes as high-efficiency catalysts for ammonia borane hydrolysis

Developing high-activity catalysts for the hydrolysis of ammonia borane (NH3BH3; AB) is a crucial and urgent task, which is presently considered an effective strategy for hydrogen generation in the applications of portable proton exchange membrane fuel cells (PEMFCs). In this study, carbon nanotubes (CNTs) were modified by self-growth of metal-organic frameworks (MOFs) on their surfaces. As self-sacrificial templates, the carbonization of cobalt and nitrogen containing MOFs led to the modification of CNT. Subsequently, cobalt was transformed into cobalt phosphide (Co2P) via phosphatization to form Co2P/N co-decorated CNTs (NCP-CNTs). Ru/NCP-CNT catalysts were obtained by loading ruthenium nanoparticles (NPs) using a chemical reduction method and their catalytic performance for H2 production via the hydrolysis of AB was systematically investigated. Ru/NCP-CNTs exhibited excellent catalytic activity, with an initial high turnover frequency (TOF) of 193.9 molH2·molRu−1·min−1 and a low activation energy of 32.4 kJ·mol−1. The incorporation of Ru NPs and their excellent synergistic effect with the NCP-CNT supports can explain the improved performance. This work provides an updated approach for fabricating low-cost and high-efficiency catalysts for the hydrolysis of AB.

Application of a novel deep eutectic solvent modified carbon nanotube for pipette-tip micro solid phase extraction of 6-mercaptopurine

Background6-mercaptopurine (6-MP) is a chemotherapy drug mainly used to treat leukemia. It is a persistent organic pollutant and can remain in the environment for a long period of time. The presence of 6-MP in the environment poses a number of hazards and needs to be assessed to monitor its potential risk to human health and the environment. However, due to its trace amount in complicated matrices, a clean-up and preconcentration step before its determination is compulsory.ResultsAs a highly efficient adsorbent for the extrication of 6-mercaptopurine (6-MP), a novel carbon nanotube doped with camphor: decanoic acid deep eutectic solvent was synthesized and applied as a packing material for the pipette-tip micro solid phase extraction sorbent of 6-MP from tap, wastewater and seawater samples before its spectrophotometric determination. Characteristics and structure of this adsorbent was fully investigated. Factors affecting extraction, including type and volume of the eluent, ionic strength and pH of the sample solution, amount of adsorbent, and number of extraction and elution cycles were optimized using one-factor-at-a-time and response surface methodologies. The method was found to be linear in the range of 1 to 1000 µg/L with a limit of detection and quantification of 0.2 and 0.7 µg/L, respectively. Reproducibility as relative standard deviation was better than 4.6%.ConclusionApplication of deep eutectic solvent modified carbon nanotube indicated suitable microextraction results and good potential for rapid extraction of trace amounts of 6-MP from different aqueous samples. The amount of sample required for the analysis was less than 10 mL and only 1.5 mg of the adsorbent was used. The total analysis time, including extraction was less than 15 min and the adsorbent could be used for at least 10 times, without significantly losing its adsorption ability. Compared to using unmodified usual carbon nanotubes, deep eutectic solvent doped carbon nanotubes showed 19.8% higher extraction ability.

Recurrent neural network (RNN) and long short-term memory neural network (LSTM) based data-driven methods for identifying cohesive zone law parameters of nickel-modified carbon nanotube reinforced sintered nano-silver adhesives

In this paper, we presented three neural network models including deep neural network (DNN), recurrent neural network (RNN), and long short-term memory neural network (LSTM), which are proposed to predict the cohesive zone parameter of sintered silver DCB joint with different contents of nickel modified carbon nanotube, thus reducing the complexity of CZM parameter acquisition for nanoparticle reinforced adhesive. The bilinear CZM model is used as the prediction target model for sintered silver joints with different contents of nickel-modified carbon nanotube filler, and data sets suitable for different networks are established through experimental and numerical simulation results. Three kinds of networks are trained based on the optimized hyperparameters obtained from the Bayesian hyperparameters tuning process. The results show that DNN, RNN, and LSTM frameworks can all predict CZM parameters of nanoparticle-reinforced sintered silver adhesive through load-displacement curves. Based on loss analysis and statistical indicator comparison after K-fold cross-validation, the RNN and LSTM models have better prediction accuracy and performance than the DNN model, and the accuracy of the LSTM model is further improved compared with the DNN model. RNN and LSTM models have high prediction accuracy and stronger recognition ability for the time series data, they can be used as suitable alternative models for inverse recognition of CZM parameters of nanoparticle-reinforced adhesives, and have broad application prospects.

Enhanced degradation and removal of ciprofloxacin and ofloxacin through advanced oxidation and adsorption processes using environmentally friendly modified carbon nanotubes.

This study explores the utilization of adsorption and advanced oxidation processes for the degradation of ofloxacin (OFL) and ciprofloxacin (CIP) using a green functionalized carbon nanotube (MWCNT-OH/COOH-E) as adsorbent and catalyst material. The stability and catalytic activity of the solid material were proved by FT-IR and TG/DTG, which also helped to elucidate the reaction mechanisms. In adsorption kinetic studies, both antibiotics showed similar behavior, with an equilibrium at 30min and 60% removal. The adsorption kinetic data of both antibiotics were well described by the pseudo-first-order (PFO) model. Different advanced oxidation processes (AOPs) were used, and the photolytic degradation was not satisfactory, whereas heterogeneous photocatalysis showed high degradation (⁓ 70%), both processes with 30min of reaction. Nevertheless, ozonation and catalytic ozonation have resulted in the highest efficiencies, 90%, and 70%, respectively, after 30-min reaction. For AOP data modeling, the first-order model better described CIP and OFL in photocatalytic and ozonation process. Intermediates were detected by MS-MS analysis, such as P313, P330, and P277 for ciprofloxacin and P391 and P332 for ofloxacin. The toxicity test demonstrated that a lower acute toxicity was observed for the photocatalysis method samples, with only 3.1 and 1.5 TU for CIP and OFL, respectively, thus being a promising method for its degradation, due to its lower risk of inducing the proliferation of bacterial resistance in an aquatic environment. Ultimately, the analysis of MWCNT reusability showed good performance for 2 cycles and regeneration of MWCNT with ozone confirmed its effectiveness up to 3 cycles.

Enhancing thermal conductivity and electromagnetic shielding performance of Ni-CNT/Al2O3/PVDF composite film with a multi-layered structure

To develop thermal interface materials with both high thermal conductivity and electromagnetic interference shielding, the polyvinylidene fluoride (PVDF) composite film was prepared by electrospinning and hot-pressing, using strategies of multi-layered structure and two fillers synergy of nickel modified carbon nanotube (Ni-CNT) and Al2O3 microspheres. The composite film consisted of a Ni-CNT filled PVDF electrospun fiber film as the top and bottom surface layers, and a PVDF electrospun fiber film electrostatically adsorbing Al2O3 microspheres and surface-sprayed with Ni-CNT as the middle layer. At a 20 wt% Ni-CNT in the surface layers and a 16.7 wt% Al2O3 and 5 wt% Ni-CNT in the middle layer, the composite film with a thickness of 0.1 mm exhibited optimal performances with electromagnetic wave shielding efficiency of 65 dB in the frequency range of 8.2–12.4 GHz, with 86% of the electromagnetic waves being absorbed. At the same time, the composite film had a high in-plane thermal conductivity of 4.02 W m−1 K−1, while maintaining a tensile strength of 25 MPa and flexibility.

A highly-sensitive electrochemical sensor based on Ni nanoparticles modified carbon nanotubes/sulfonated reduced graphene oxide for the detection of capsaicinoids in leisure sauced meat products

Unclear labeling of spiciness degrees on leisure sauced meat products is prone to resulting in customer complaints and commercial disputes. The content of capsaicinoids is the basis for evaluating the spiciness of food. In this work, an electrochemical sensor based on nickel nanoparticles modified carbon nanotubes (Ni-CNTs) and sulfonated reduced graphene oxide (S-rGO) was developed for the rapid detection of capsaicinoids content in leisure sauced meat products. The linear ranges of capsaicins are 0.01–100 μmol/L with ultra-low detection limits of 1 nmol/L. The outstanding performances are primarily due to the synergistic effect between Ni-CNTs and S-rGO. This effect not only created a three-dimensional stacked structure that improved the electrochemically active surface area, but also generated an internal electric field that improved the charge transfer rate. This work provides a basis for standardized evaluation of spiciness.