Carbon Nanotube Hybrid Research Articles

Deflection responses of damaged hybrid (carbon nanotubes – luffa) composite structure: An experimental verification

AbstractThe deflection responses of intact and damaged hybrid curved shell structures are investigated numerically and experimentally under mechanical loading conditions. The damaged hybrid composite is numerically modelled in MATLAB using higher‐order mid‐plane polynomials and finite element technique. The consistent characteristics and model accuracy have been established by comparing the consequences to those accessible in the existing article. Additionally, the study examined experimentally and computationally obtained elastic properties from the DIGIMAT tool, substantially boosting the extent and reliability of the analysis. Finally, numerous examples are provided to illustrate the impact of damage, considering various parametric input constraints, on the deflection characteristics of the hybrid composite.

Achievements, challenges, and stability of layer double hydroxide and carbon nanotube hybrid electrode materials for clean and sustainable energy storage supercapacitor application: an extensive review

The graphical abstract illustrates the use of LDH/CNT: a low cost, flexible and sustainable rapid energy storage and release supercapacitor.

Enhancing thermal conductivity and electromagnetic shielding performance of polyvinylidene fluoride composite film with densified filler network by hot imprinting

AbstractA simple strategy of hot imprinting was proposed to construct a densified filler network for the preparation of electrospun polyvinylidene fluoride (PVDF) composite film with high thermal conductivity and electromagnetic shielding performance. First, continuous imprints were obtained by hot pressing on the surface of PVDF fiber film using a metal mesh as a stencil. Magnetic Fe3O4‐modified carbon nanotubes (Fe3O4@CNTs) were then loaded onto the surface of the films using an impregnation method. Finally, the Fe3O4@CNTs/PVDF composite film was fabricated by a three‐layer hot pressing process. The mesh size and filler loading cycles have an important effect on the resulting performance of the composite film. Under the optimal conditions of 1 × 2 mesh size and five loading cycles, the thermal conductivity of the composite film with only 5.16 wt% CNTs content, was 1.91 W/mK, which is an improvement of 51.6% compared to that of the non‐imprinted composite film. The electromagnetic shielding effectiveness of the composite film reached 28.6 dB. This strategy provides a feasible approach for the large‐scale production of high‐performance thermal interface materials.Highlights Enhancing continuous filler network in PVDF composite film by hot imprinting. Developing carbon nanotube and Fe3O4 hybrid fillers with a heterogeneous structure. Achieving significant improvements in TC and EMI SE of the composite film. Offering large‐scale production methods of high‐performance thermal interface materials.

Ultrathin MWCNT/Ti3C2Tx Hybrid Films for Electromagnetic Interference Shielding.

The disordered assembly and low conductivity of carbon nanotubes are the main problems that limit the application of electromagnetic interference (EMI) shielding. In this work, an ordered lamellar assembly structure of multiwalled carbon nanotube/Ti3C2Tx (MWCNT/Ti3C2Tx) hybrid films was achieved by vacuum-assisted filtration through the hybridization of Ti3C2Tx nanosheets and carbon nanotubes, where carbon nanotubes were tightly sticking on the surface of Ti3C2Tx nanosheets via physical adsorption and hydrogen bonding. Compared with the pure carbon nanotubes films, the hybrid MWCNT/Ti3C2Tx films achieved a significant improvement in conductivity of 452.5 S/cm and EMI shielding effectiveness (SE) of 44.3 dB under 50 wt% Ti3C2Tx with a low thickness (8.6 μm) and orderly lamellar stacking structure, which finally resulted in high specific SE (SSE/t, SE divided by the density and thickness) of 55,603.1 dB∙cm2∙g-1.

Mechanical Properties of High-Volume Fly Ash Mortar Modified by Hybrid Carbon Nano Tube and Graphene Oxide

The effect of combined nano materials on mechanical properties of high-volume fly ash mortar (HVFAM) was carried out in this investigation. The characteristics of HVFAM mixes were first evaluated using slump flow tests. Then, the mechanical properties of HVFAM including the measurement of setting time and the development of early-age compressive strength were performed. Structural changes during hydration were analyzed using FTIR analysis. The study utilized fly ash (FA) as a 60% replacement for cement, with the addition of 0.01% carbon nanotubes (CNT) and graphene oxide (GO) with five different dosages ranging from 0.01% to 0.05%. Results of study showed that the incorporation of hybrid CNT and GO significantly affected the mechanical properties of HVFAM. Specifically, increased of CNT and GO contents lead to significant reduction in both workability and setting time of HVFAM, with a more pronounced reduction in final setting time compared to initial setting time. The development of early-age strength of HVFAM improved by 15.8% with the highest 28 day-strength increasing by approximately 23% at 0.01% CNT and 0.03% GO dosages. FTIR analysis confirmed that the improved early-age strength was attributed to the accelerated hydration of cement caused by the seeding effect. The outcome of the study provides a suitable approach for the development of eco-friendly materials with improved mechanical properties that could be effectively used for HVFAM.

Ultrafast Microwave-Synthesized 2D/1D MnO2/Carbon Nanotube Hybrid for Bilirubin Detection in Simulated Blood Serum.

Hybridization of carbon nanotubes (CNTs) and manganese dioxide (MnO2) integrates the biocompatibility and outstanding electrocatalytic activity of MnO2 with the exceptional conductivity of CNTs, thus providing a superior synergistic sensing platform for the detection of biomolecules. However, the existing methods for synthesizing MnO2/CNT hybrids are complex and inefficient, resulting in low yields and limited surface functionalities. Hence, in this study, we present a low-cost and ultrafast solid-phase synthesis of the MnO2/CNT hybrid using a facile microwave technique to detect a crucial biomolecule bilirubin. The successful synthesis of the MnO2/CNT hybrid is confirmed through characteristic Raman and X-ray diffraction peaks, while morphology is analyzed by imaging techniques such as FESEM and HRTEM. The MnO2/CNT/nickel foam (NF) sensor is thereafter used for the electrochemical detection of bilirubin. The sensor demonstrates a wide linear detection range from 10 nM to 1 mM, with a sensitivity of 6.87 mA nM-1 cm-2 toward bilirubin, as determined through the differential pulse voltammetry technique. The lower limit of detection is noted at 3.3 nM (=3.3 S/m). Furthermore, the as-fabricated sensor showcases high selectivity against the interfering species. Real-time analysis conducted in simulated blood serum using the standard addition method reveals an outstanding recovery percentage of approximately 98%. The conductive MnO2/CNT hybrid interacts robustly with bilirubin, aided by the porous NF substrate for stability, catalytic activity, and rapid electron transfer, enabling sensitive bilirubin detection. The work provides an ultrafast, low-cost, and high-yield solid-phase microwave synthesis of MnO2/CNT hybrid material and broadens its application in the detection of biological specimens for clinical diagnosis and biomedical research.

Preparation and Characterization of Graphene and Carbon Nanotube Hybrid Polydimethylsiloxane Composites for Protective Coating Applications

In this work, the synergistic effect of graphene nanosheets (GNs), as well as multiwalled carbon nanotubes (MWCNTs), as reinforcing agents of polydimethylsiloxane (PDMS) was investigated, in order to explore the possibilities of designing composite materials, tailored for use in the field of coatings, which might be, in fact, a very interesting application. It was shown that the addition of GNs and MWCNTs in PDMS matrices significantly improves the thermal stability of the obtained nanocomposites, especially those reinforced exclusively with GNs. The tensile tests indicated that strength increased for all the examined composites. It was also observed that the Young’s moduli had an increasing trend, with the exception of the composites containing only GNs, while those reinforced solely with MWCNTs exhibited the best performance. The O2 permeability measurements revealed that the highest reduction in the permeability was observed in GN-MWCNT/PDMS composite membranes, in comparison to those reinforced only with graphene or carbon nanotubes. Dielectric relaxation spectroscopy showed that all the examined composites, and especially those of MWCNTs, possess electrical conductivity, apart from the samples reinforced exclusively with graphene. The electromagnetic shielding effectiveness was also improved at higher filler loadings, which is more evident in composites reinforced with MWCNTs. It was concluded that the improved properties of the above studied hybrid composites make them suitable for protective coating applications.

Pure organic dual phase polypyrrole wrapped single-walled carbon nanotube hybrid nano-photocatalyst for solar hydrogen generation

Pure organic dual phase polypyrrole wrapped single-walled carbon nanotube hybrid nano-photocatalyst for solar hydrogen generation

Deformation coordination behaviors and microstructure evolution of SiC and carbon nanotubes hybrid reinforced aluminum matrix composite during hot working

Deformation coordination behaviors and microstructure evolution of SiC and carbon nanotubes hybrid reinforced aluminum matrix composite during hot working

Enhanced electrochemical sensor based on Uio-66-NH2/carbon nanotubes hybrid for selective detection of ofloxacin

Enhanced electrochemical sensor based on Uio-66-NH2/carbon nanotubes hybrid for selective detection of ofloxacin

Mercury (II) sensor based on nanosilver/chitosan modified screen-printed carbon electrode

This study introduces a highly sensitive platform for ultratrace mercury [Hg (II)] detection, utilizing a screen-printed carbon electrode (SPCE) modified with silver nanoparticles (AgNPs), chitosan (CS), and carbon nanotubes (CNTs). The AgNPs were synthesized using a green method incorporating CS and CNT hybrids, leading to their immobilization on the CNT sidewalls, resulting in nanoscale silver electrode arrays on the SPCE. Detection of Hg (II) involved the formation of Hg/Ag amalgam on the AgNPs/CS/CNT-modified SPCE surface by depositing mercury species onto elemental mercury. Hg (II) detection successfully occurred through the stripping of both Hg0 and Ag0 at a potential of +0.16 V in a supporting electrolyte (0.10 M HCl and 0.10 M KCl). This newly established detection method demonstrates exceptional selectivity and sensitivity, featuring a remarkable linear range for Hg (II) concentration from 1.0 nM to 12.6 nM, with an impressive correlation coefficient (R2) of 0.982 (n = 13) and a low detection limit of 0.4 nM. The designed electrode effectively measured Hg (II) levels in textile samples, yielding acceptable recovery results, while also exhibiting remarkable reproducibility and precision. This work presents a novel, highly sensitive, and selective approach for ultratrace Hg (II) detection, with promising applications in environmental monitoring and analytical chemistry.

A high‐performance stretchable strain sensors with hierarchically gradient morphology of filler network

AbstractIn recent years, stretchable strain sensors have received increasing attention in areas such as human motion detection and soft robotics. However, how to simultaneously improve the sensitivity and operating range of them remains one of the most important challenges. In order to solve this challenge, in this study, nickel‐coated graphite (NCG)/carbon nanotubes (CNTs) hybrid conductive networks of stretchable strain sensors PNCs with graded degree of sedimentation were constructed in PDMS using the sedimentation method. Due to the difference in packing density and packing morphology, NCG mainly stays in the middle and lower layers, forming a partially‐sedimented state, whereas the CNTs are close to uniformly dispersed, and such partially settled NCG network is especially critical. Based on this, the obtained composite PNCs have high sensitivity, with a GF value as high as 1.48 × 104 in the 0%–25% strain range and an operating range of 224.8%, which achieves a good recognition and detection of the full range of human body movements. This work provides a new process for the preparation of high‐performance stretchable strain sensors.

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.

Selective Synthesis of 3D Aligned VO2 and V2O5 Carbon Nanotube Hybrid Materials by Chemical Vapor Deposition.

3D carbon nanotube hybrid materials containing VO2 and V2O5 evenly distributed onto vertically aligned carbon nanotubes (VACNTs) is reported. Adjustable loading of particles in controllable sizes and shapes onto the VACNTs was developed via a stepwise chemical vapour deposition (CVD) approach. Solid VO(acac)2 is chosen as vanadium source. CO2 acts as reactive gas for the pre-functionalisation of the VACNTs. The process temperature was identified as key parameter to control the deposited vanadium oxide phase. A temperature of 550 °C results in monoclinic VO2, while 600 °C results in the deposition of V2O5 onto the VACNT support. The morphology and the amount of deposited material was found to be dependent on the reactor dimensions and the degree of functionalisation of the carbon support. An increase of the D/G ratio of the VACNT from 0.75 to 1.08 caused by a CO2 treatment step within the process led to an increase of the particle coverage from a scarce coverage without prior CO2 treatment to a dense coverage of the VACNT support after 15 min of CO2 exposure time. Size and crystallinity of the as deposited particles can be further adjusted by a controlled heat treatment after VO(acac)2 precursor deposition.

Single-walled carbon nanotubes hybrid carbon materials sensor for simultaneous detection of chloramphenicol and furazolidone in food samples

Single-walled carbon nanotubes hybrid carbon materials sensor for simultaneous detection of chloramphenicol and furazolidone in food samples

Single walled carbon nanotubes/ZnO nanowires heterostructure array for NO2 gas sensing at low ppm levels

A layer-by-layer ZnO nanowire (NW)-Single Walled Carbon Nanotube (CNT) hybrid gas sensor has been proposed for effective detection of NO2 gas under a low exposure limit of 5 ppm. The fabricated hybrid sensor displayed good sensor response (S %), good selectivity and fast response time towards the target gas. S % value of 36.4 % under 5 ppm NO2 level at 250 °C and good selectivity response towards different interfering gases like SO2, CO and H2 have been observed. Meanwhile, fast response time values of 44.08 s (response) and 62.11 s (recovery) were observed at 300 °C under 5 ppm NO2 level. The sensor baseline resistance of the hybrid heterostructure (HS) was also found to be lower when compared to that of a bare ZnO NW sensor. In addition, the presence of Single Walled CNT in the HS was also shown to reduce the operational temperature of the sensor. Temperature played a significant role by controlling the adsorption and desorption kinetics of gas molecules on the surface. Moreover, the formation of p-n interface between Single Walled CNT (p-type) and ZnO NW (n-type) might have modulated the potential charge barrier on interacting with the adsorbed gases which inturn might have impacted the response of the hybrid sensor. In addition, the large surface areas offered by both NWs and nanotubes might have improved the gas adsorption capability thereby enhancing the overall hybrid sensor’s response.

Enhancing thermo-physical properties of hybrid nanoparticle-infused medium temperature organic phase change materials using graphene nanoplatelets and multiwall carbon nanotubes

Phase change materials (PCMs) have emerged as an intriguing option for the storage of thermal energy because of their remarkable capacity to store latent heat. However, the practical application of these materials is hindered by their low thermal conductivity and limited photo-absorbance. For this investigation, graphene nanoplatelets (GNP) and multiwall carbon nanotubes (MWCNT) hybrid nanoparticles were disseminated in RT-54HC organic PCMs at different weight fractions. The nanoparticles were incorporated into the base PCMs using a melt blending technique. Based on the findings, one combination of GNP to MWCNT in a 0.25:0.75 ratio has shown the highest thermal conductivity, with an increase of 40% (0.28 Wm−1 K−1) compared to other hybrid combinations. This breakthrough could potentially open new avenues in the field of thermal energy storage. The chemical stability of the hybrid nanoparticle dispersed composites was assessed through FTIR analysis. In addition, the composites exhibited excellent thermal stability, maintaining their structural integrity even at temperatures as high as 300 ℃. The melting temperature of the composites also showed minimal variation. Based on the evaluation of latent heat enthalpy, the organic PCM known as base RT-54HC demonstrated a heat storage capacity of 230 J/g. However, the composites exhibited a slight decrease in latent heat with increasing nanoparticle weight fraction. In addition, the composite with added hybrid nanoparticles demonstrated an increase in optical absorbance, accompanied by a decrease in transmissibility. Therefore, the hybrid nano-enhanced composites have demonstrated enhanced thermo-physical properties, making them not only suitable but also highly promising for use in applications with mid-range melting temperatures.Graphical

Enhancing hydrogen evolution: Carbon nanotubes as a scaffold for Mo2C deposition via magnetron sputtering and chemical vapor deposition

This study presents an innovative approach to fabricating carbon nanotubes (CNTs) through magnetron sputtering and chemical vapor deposition (CVD). These CNTs serve as a robust structural scaffold for the deposition of molybdenum, which, through thermal annealing, becomes molybdenum carbide (Mo2C), which is highly efficient for hydrogen evolution reaction (HER). Our investigation delves into the physical and chemical attributes of these electrodes, revealing insights into the functionality of Mo2C on CNTs hybrid structures. Chemical characterization confirms the exceptional performance of the electrode. Our Mo2C on CNT hybrid system showcases remarkable electrocatalytic activity, with an onset potential of 103 mV at 1 mA/cm2 and an overpotential of 176 mV at 10 mA/cm2. Further validation comes from tests revealing a Tafel slope of 95 mV/dec, affirming its superiority in facilitating HER. Unparalleled combination of low charge transfer resistance and accelerated reaction kinetics, Mo2C on CNTs hybrid structure is poised to significantly enhance HER activity.

Improvement of Electrical and Thermal Properties of Carbon Nanotube Sheets by Adding Silver Nanowire and Mxene for an Electromagnetic-Interference-Shielding Property Study.

Hybrid carbon nanotube (CNT) sheets were fabricated by mixing CNTs with silver nanowires (AgNWs) and MXene to study their electromagnetic-interference (EMI)-shielding properties. CNT/AgNW and CNT/MXene hybrid sheets were produced by ultrasonic homogenization and vacuum filtration, resulting in free-standing CNT sheets. Three different weight ratios of AgNW and MXene were added to the CNT dispersions to produce hybrid CNT sheets. Microstructure characterization was performed using scanning electron microscopy, and the Wiedemann-Franz law was used to characterize transport properties. The resulting hybrid sheets exhibited improved electrical conductivity, thermal conductivity, and EMI-shielding effectiveness compared to pristine CNT sheets. X-band EMI-shielding effectiveness improved by over 200%, while electrical conductivity improved by more than 1500% in the hybrid sheets due to a higher charge-carrier density and synergistic effects between nanomaterials. The addition of AgNW to CNT sheets resulted in a large improvement in electrical conductivity and EMI shielding; however, this may also result in increased weight and sample thickness. Similarly, the addition of MXene to CNT sheets may result in an increase in weight due to the presence of the denser MXene flakes.

Silver Oxide Nanoparticle Decorated Carbon Nanotube as Efficient Electron Gun

AbstractAlthough there have been numerous great field emission reports of pure and hybrid carbon nanotubes (CNTs) with ultra‐low turn‐on field and ultra‐high emission stability, practically all of the reports indicate concern about CNT manufacture on a large scale. This is due to the fact that CNT experiments require high pressure, temperature, metal catalysis, and an inert environment, and even after meeting all of these perfect conditions, the yield is quite low. Furthermore, as CNT is relatively inert in nature, it is nearly hard to make it reactive with any other metal without adequate functionalization. Keeping this in mind, this work reports the synthesis of CNT in amorphous form by a simple low‐temperature solid‐state reaction between ammonium chloride and ferrocene. The as‐synthesized CNT is further functionalized by silver oxide nanoparticle without additional functionalization. X‐ray diffraction (XRD) confirms the proper phase formation as well as the successful functionalization of the pure and hybrid sample, electron microscopic images confirm the successful functionalization of the as‐prepared CNT whereas Fourier transformed infrared (FTIR) spectroscopic analysis gives the ideas about different bonding present in all the samples. It has been found that the hybrid sample gives much better field emission performance compare to the pure CNT with betterment in both turn‐on field and enhancement factor more than 100%. The betterment is believed to be due to the favorable band bending, larger number of emission sites, and sharp curvature of the silver particles.