Electrochemical Impedance Studies on Single and Multi-Walled Carbon Nanotubes—Polymer Nanocomposites for Biosensors Development

Even though the characteristics of polymer materials are sensitive to temperature, the mechanical properties of polymer nanocomposites have rarely been studied before, especially for the fatigue behavior of hybrid polymer nanocomposites. Hence, the tensile quasi-static and fatigue tests for the epoxy nanocomposites reinforced with multi-walled carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) were performed at different temperatures in the study to investigate the temperature-dependent synergistic effect of hybrid nano-fillers on the studied properties. The temperature and the filler ratio were the main variables considered in the experimental program. A synergistic index was employed to quantify and evaluate the synergistic effect of hybrid fillers on the studied properties. Experimental results show that both the monotonic and fatigue strength decrease with increasing temperature significantly. The nanocomposites with a MWCNT (multi-walled CNT): GNP ratio of 9:1 display higher monotonic modulus/strength and fatigue strength than those with other filler ratios. The tensile strengths of the nanocomposite specimens with a MWCNT:GNP ratio of 9:1 are 10.0, 5.5, 12.9, 23.4, and 58.9% higher than those of neat epoxy at −28, 2, 22, 52, and 82 °C, respectively. The endurance limits of the nanocomposites with this specific filler ratio are increased by 7.7, 26.7, 5.6, 30.6, and 42.4% from those of pristine epoxy under the identical temperature conditions, respectively. Furthermore, the synergistic effect for this optimal nanocomposite increases with temperature. The CNTs bridge the adjacent GNPs to constitute the 3-D network of nano-filler and prevent the agglomeration of GNPs, further improve the studied strength. Observing the fracture surfaces reveals that crack deflect effect and the bridging effect of nano-fillers are the main reinforcement mechanisms to improve the studied properties. The pullout of nano-fillers from polymer matrix at high temperatures reduces the monotonic and fatigue strengths. However, high temperature is beneficial to the synergistic effect of hybrid fillers because the nano-fillers dispersed in the softened matrix are easy to align toward the directions favorable to load transfer.

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Electrodeposition of Sn and Sn Composites with Carbon Materials Using Choline Chloride-Based Ionic Liquids

Coatings ◽

10.3390/coatings9120798 ◽

2019 ◽

Vol 9 (12) ◽

pp. 798

Author(s):

Ana T. S. C. Brandão ◽

Liana Anicai ◽

Oana Andreea Lazar ◽

Sabrina Rosoiu ◽

Aida Pantazi ◽

...

Keyword(s):

Carbon Nanotubes ◽

Carbon Materials ◽

Electrochemical Impedance ◽

Choline Chloride ◽

Composite Films ◽

Growth Stages ◽

Initial Growth ◽

Sem Images ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

Nano carbons, such as graphene and carbon nanotubes, show very interesting electrochemical properties and are becoming a focus of interest in many areas, including electrodeposition of carbon–metal composites for battery application. The aim of this study was to incorporate carbon materials (namely oxidized multi-walled carbon nanotubes (ox-MWCNT), pristine multi-walled carbon nanotubes (P-MWCNT), and reduced graphene oxide (rGO)) into a metallic tin matrix. Formation of the carbon–tin composite materials was achieved by electrodeposition from a choline chloride-based ionic solvent. The different structures and treatments of the carbon materials will create metallic composites with different characteristics. The electrochemical characterization of Sn and Sn composites was performed using chronoamperometry, potentiometry, electrochemical impedance, and cyclic voltammetry. The initial growth stages of Sn and Sn composites were characterized by a glassy-carbon (GC) electrode surface. Nucleation studies were carried out, and the effect of the carbon materials was characterized using the Scharifker and Hills (SH) and Scharifker and Mostany (SM) models. Through a non-linear fitting method, it was shown that the nucleation of Sn and Sn composites on a GC surface occurred through a 3D instantaneous process with growth controlled by diffusion. According to Raman and XRD analysis, carbon materials were successfully incorporated at the Sn matrix. AFM and SEM images showed that the carbon incorporation influences the coverage of the surface as well as the size and shape of the agglomerate. From the analysis of the corrosion tests, it is possible to say that Sn-composite films exhibit a comparable or slightly better corrosion performance as compared to pure Sn films.

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Aerosol Emission Monitoring and Assessment of Potential Exposure to Multi-walled Carbon Nanotubes in the Manufacture of Polymer Nanocomposites

The Annals of Occupational Hygiene ◽

10.1093/annhyg/mev044 ◽

2015 ◽

Vol 59 (9) ◽

pp. 1135-1151 ◽

Cited By ~ 12

Author(s):

Drew Thompson ◽

Sheng-Chieh Chen ◽

Jing Wang ◽

David Y.H. Pui

Keyword(s):

Carbon Nanotubes ◽

Polymer Nanocomposites ◽

Potential Exposure ◽

Aerosol Emission ◽

Emission Monitoring ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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Cost-Effective Potentiometric Platforms Modified with Multi-Walled Carbon Nanotubes (MWCNTs) and Based on Imprinted Receptors for Fluvoxamine Assessment

Polymers ◽

10.3390/polym12030673 ◽

2020 ◽

Vol 12 (3) ◽

pp. 673

Author(s):

Heba M. Hashem ◽

Saad S. M. Hassan ◽

Ayman H. Kamel ◽

Abd El-Galil E. Amr ◽

E. M. AbdelBary

Keyword(s):

Carbon Nanotubes ◽

Electrochemical Impedance ◽

Biological Fluids ◽

Pharmaceutical Preparations ◽

Cost Effective ◽

Hplc Method ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Screen Printed

A simple, efficient and reliable analytical method was developed and used for the determination of the fluvoxamine drug (FLV) in pharmaceutical preparations and biological fluids. The method is based on the cost-effective screen-printed platform for the potential transduction of the drug. Host-tailored molecular imprinting polymer (MIP) was integrated with the potentiometric platform as a recognition receptor, in which FLV, acrylamide (AAm), ethylene glycol dimethacrylate (EGDMA) and acetonitrile were used as a template, functional monomer, cross-linker, and solvent, respectively. MIP particles were dispersed in plasticized poly (vinyl chloride) (PVC) and the membrane was drop-casted on carbon screen-printed electrode. The MIP, in addition to non-imprinted polymers (NIP), was characterized and the binding experiment revealed high affinity and adsorption capacity of MIP towards FLV. The proposed sensor displayed near-Nernstian cationic slope of 55.0 ± 0.8 mV/decade (r2 = 0.999) with a low detection limit of 4.8 × 10−6 mol/L over a wide pH range (3.0–8.5). The electrochemical features of the proposed sensors including electrochemical impedance spectroscopy (EIS) and chronopotentiometry measurements (CP) in the presence of multi-walled carbon nanotubes (MWCNTs) as a solid contact transducer were also investigated. The applications of the proposed sensor for the determination of FLV in different dosage forms with recovery values (98.8%–101.9%) and (97.4%–101.1%), respectively compared with the reference HPLC method with acceptedFandt-student tests values at the 95% confidence level.

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Multi-walled carbon nanotubes/nano-Ag-TiO2 membrane DNA electrochemical biosensor

10.1101/618488 ◽

2019 ◽

Author(s):

Zhongguo Zheng ◽

Lisa Schultz ◽

John Smith

Keyword(s):

Carbon Nanotubes ◽

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Electrochemical Biosensor ◽

Electrochemical Impedance ◽

Carbon Paste ◽

Dna Electrochemical Biosensor ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Paste Electrode

AbstractA highly sensitive DNA electrochemical biosensor was prepared based on multi-walled carbon nanotube/nano-Ag-TiO2 composite membrane. The Ag-TiO2 composite is mixed with a suitable amount of multi-walled carbon nanotubes (MWNT) dispersed in N,N-dimethylformamide to form a uniform and stable mixed solution, which is applied onto the surface of the bare carbon paste electrode. A MWNT/Ag-TiO2 modified carbon paste electrode was prepared. The large specific surface area and good electron transport properties of carbon nanotubes have a good synergistic effect on the good biocompatibility of Ag-TiO2 nanocomposites and excellent adsorption capacity of DNA, which significantly improves the immobilization and DNA hybridization of DNA probes. Detection sensitivity. The preparation of the sensing membrane and the immobilization and hybridization of DNA were characterized by cyclic voltammetry and electrochemical impedance spectroscopy. The exogenous glufosinate acetyltransferase gene fragment of transgenic plants was detected by electrochemical impedance spectroscopy. The linear range was 1. 0 × 10 - 11 ∼1. 0 × 10 - 6 mol / L. The detection limit was 3. 12 × 10 - 12 mol / L.

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Preparation of Molecularly Imprinted Polypyrrole and Carbon Nanotubes Film Modified Electrode for Dopamine Recognition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.578.105 ◽

2012 ◽

Vol 578 ◽

pp. 105-108 ◽

Cited By ~ 1

Author(s):

Fei Fei Zhang ◽

Zong Hua Wang ◽

Jian Fei Xia ◽

Yan Zhi Xia ◽

Feng Cai ◽

...

Keyword(s):

Carbon Nanotubes ◽

Modified Electrode ◽

High Selectivity ◽

Electrochemical Impedance ◽

Good Sensitivity ◽

Optimum Conditions ◽

Molecularly Imprinted ◽

Multi Walled Carbon Nanotubes ◽

Overoxidized Polypyrrole ◽

Walled Carbon Nanotubes

A novel film of overoxidized polypyrrole and carboxylic multi-walled carbon nanotubes (c-MWNTs) was fabricated with molecular imprinted technique for dopamine by a direct and facile electropolymerization method. The resulting modified electrode surface was characterized with electrochemical impedance spectroscopy and Fourier transform infrared spectroscopy. The results demonstrated that the modified electrode not only possessed a good sensitivity but also exhibited a high selectivity toward DA which making anodic potential difference of DA and AA is 318 mV in DPV. Under the optimum conditions, the linear range of the dopamine biosensor ranges from 5.0×10−8 to 6.0×10−6 mol/L with a detection limit of 5.0×10−9 mol/L

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Polymer nanocomposites reinforced with multi-walled carbon nanotubes for semiconducting layers of high-voltage power cables

Polymer International ◽

10.1002/pi.2696 ◽

2010 ◽

Vol 59 (1) ◽

pp. 100-106 ◽

Cited By ~ 40

Author(s):

Kwang-Un Jeong ◽

Jee Young Lim ◽

Jong-Young Lee ◽

Seong Lak Kang ◽

Changwoon Nah

Keyword(s):

Carbon Nanotubes ◽

Polymer Nanocomposites ◽

High Voltage ◽

Power Cables ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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Metamaterial Behavior of Polymer Nanocomposites Based on Polypropylene/Multi-Walled Carbon Nanotubes Fabricated by Means of Ultrasound-Assisted Extrusion

Materials ◽

10.3390/ma9110923 ◽

2016 ◽

Vol 9 (11) ◽

pp. 923 ◽

Cited By ~ 5

Author(s):

Juan Pérez-Medina ◽

Miguel Waldo-Mendoza ◽

Víctor Cruz-Delgado ◽

Zoe Quiñones-Jurado ◽

Pablo González-Morones ◽

...

Keyword(s):

Carbon Nanotubes ◽

Polymer Nanocomposites ◽

Multi Walled Carbon Nanotubes ◽

Ultrasound Assisted ◽

Walled Carbon Nanotubes

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Preparation and characterization of high-performance wood polymer nanocomposites using multi-walled carbon nanotubes

Journal of Composite Materials ◽

10.1177/0021998316674265 ◽

2016 ◽

Vol 51 (9) ◽

pp. 1187-1195 ◽

Cited By ~ 4

Author(s):

Alperen Kaymakci ◽

Nadir Ayrilmis ◽

Turker Gulec ◽

Mursit Tufan

Keyword(s):

Carbon Nanotubes ◽

Maleic Anhydride ◽

Polymer Nanocomposites ◽

Wood Flour ◽

Scanning Calorimetry ◽

Industrial Grade ◽

Wood Polymer ◽

Multi Walled Carbon Nanotube ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

Effect of industrial grade multi-walled carbon nanotubes on mechanical, decay, and thermal properties of wood polymer nanocomposites was investigated. To meet this objective, pine wood flour, polypropylene with and without coupling agent (maleic anhydride grafted polypropylene), and multi-walled carbon nanotube (0, 1, 3, 5 wt%) were compounded in a twin screw co-rotating extruder. The mass ratio of the wood flour to polypropylene was 50/50 (w/w) in all compounds. Test specimens were produced using injection molding machine from the pellets. The flexural and tensile properties, biological durability, and thermal analysis (thermogravimetric analysis and differential scanning calorimetry) of the nanocomposites were investigated. The flexural and tensile properties of the wood polymer nanocomposites increased with increasing content of the industrial grade multi-walled carbon nanotubes (from 1 to 5 wt%) and maleic anhydride grafted polypropylene (3 wt%). The mass loss rates of the wood polymer nanocomposites decreased with increasing amounts of the maleic anhydride grafted polypropylene and industrial grade multi-walled carbon nanotube. The differential scanning calorimetry analysis showed that the melt crystallization enthalpies of the wood polymer nanocomposites increased with increasing amount of the industrial grade multi-walled carbon nanotubes. The increase in the Tc indicated that the industrial grade multi-walled carbon nanotubes were the efficient nucleating agent for the wood polymer nanocomposites.

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