Carbon Nanotube Nanocomposite Films Research Articles

A novel enzymeless electrochemical sensor based on Ni(OH)2–NiO(OH) nanoelectrocatalyst for sensitive and selective detection of uric acid in PBS simulated body fluid

Neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, and Huntington's disease are increasing worldwide. Therefore, the development of a low-cost, highly stable, and portable device for rapid and accurate risk assessment of relevant biomarkers, especially uric acid (UA), by electrochemical detection is currently attracting much attention. Herein, an electrochemical enzymeless UA sensor based on highly active Ni(OH)2–NiO(OH) nanoelectrocatalyst decorated on polyaniline–carbon nanotubes (PANI-CNTs) nanocomposite film, which was modified on a commercial screen-printed carbon electrode (SPCE) by electrodeposition method for sensitive and selective detection of UA. The sensing behavior of the modified electrode (named Ni(OH)2–NiO(OH)/PANI-CNTs/SPCE) is examined in a simulated body fluid (phosphate buffer solution-PBS, 0.01 M, pH 7.4) using differential pulse voltammetry (DPV) technique. The obtained results showed that the Ni(OH)2–NiO(OH)/PANI-CNTs/SPCE electrode exhibited outstanding electrocatalytic performance for the detection of UA at low potential (0.33 V vs. Ag/AgCl) without exhibiting interfering signals of dopamine (DA), glucose (Glu), ascorbic acid (AA) and urea. The sensor exhibited extra high sensitivity (386.8 μA mM−1 cm−2), high selectivity, good reproducibility, and durable stability with the ability to detect UA at both low (5–100 μM) and high (100–800 μM) levels with a very low detection limit down to 0.11 μM (individual detection of UA) and 0.29 μM (detection of UA in presence of DA) in a simulated body fluid. The recovery test using the proposed electrochemical sensor showed a high recovery percentage (>99.81 %), making it a viable option for practical applications.

Customized Extrusion Nozzle Assisted Robust Nylon 6/MWCNT Nanocomposite Based Triboelectric Nanogenerators for Advanced Smart Wearables

To meet the growing demand for durable, tough, and electrically conductive polymer nanocomposites driven by the rise of smart devices, e-textiles, wearables, and advanced structures, this study offers a systematic approach to fabricating highly robust Nylon 6/multi-walled carbon nanotubes (MWCNTs) nanocomposite films and fibers. The robustness of the nanocomposite is achieved through a simple straightforward approach involving the selective surface functionalization of MWCNTs with oxygen plasma-assisted tetraethylenepentamine grafting (O2T-MWCNTs) and melt-blending these MWCNTs with Nylon 6 under optimized conditions. The mixture is then processed through a specially designed narrow convergent nozzle attached to the extruder die. The die facilitates the alignment of the CNTs into the matrix in the flow direction and increases the composite strength. The incorporation of just 1 wt% of O2T-MWCNTs into Nylon 6 results in a nanocomposite with a remarkable enhancement, demonstrating a 93.25 % increase in tensile strength (T.S.), a 50.47 % increase in Young’s Modulus (E), and an outstanding 136 % increase in elongation at the break (ε) compared to neat Nylon 6, surpassing contemporary benchmarks. Importantly, this method yields a nanocomposite ∼ 30.2 % stronger than the conventional melt-blending process without a nozzle. When fabricating a triboelectric nanogenerator (TENG) with the nanocomposite, exceptional performance was observed, with an output voltage of 105.7 V, a current of 10.55 μA, and a power density of 465 mW/m2, surpassing many reported values. Moreover, the TENG displays highly stable performance through 20,000 cycles of continuous compression. The nanogenerator also exhibited outstanding capability in harvesting mechanical energy from body movements, as demonstrated by lighting various LEDs and small electronics.

Tuning thermoelectric performance with N-annulated perylene-based small molecules and single-walled carbon nanotube nanocomposite films

Two N-annulated perylene (NP)-based organic small molecules (OSMs) with end groups of di-p-tolylamine (DTA) and phenyl-di-p-tolylamine (PhDTA), namely DDTANP and DPhDTANP, are incorporated into single-walled carbon nanotubes (SWCNTs) to fabricate nanocomposite thin films for thermoelectric (TE) application. The weight ratios of OSMs to SWCNTs range from 1:1 to 1:4. The inherent planar structures of these novel OSMs facilitate strong π-π interactions and charge transfer with SWCNTs. Specifically, the DDTANP/SWCNT nanocomposite films, due to its lower HOMO, induces pronounced energy filtering and, thus, a high Seebeck coefficient (S). At the optimized weight ratio of 1:3, DDTANP/SWCNT nanocomposite thin film exhibits an electrical conductivity (σ) of 214.7 S cm−1, and S of 59.8 μV K−1. The flat structure of DPhDTANP enhances its adhesion to SWCNTs, thereby improving dispersion and increasing σ. Similarly, the DPhDTANP/SWCNT (1:3) nanocomposite thin film achieves 256.4 S cm−1, and an S of 55.8 μV K−1. The DPhDTANP/SWCNT (1:3) nanocomposite film exhibits higher σ, resulting in a power factor (PF) of 79.8 μW m−1 K−2, surpassing the PF of 76.7 μW m−1 K−2 for the DDTANP/SWCNT (1:3) nanocomposite film. These findings offer valuable insights into molecular design for SWCNTs-based composite TE research and contributed to enhancing TE applications.

Development of integrated smartphone/resistive biosensor for on-site rapid environmental monitoring of organophosphate pesticides in food and water

Organophosphate (OP) pesticides remain a worldwide health concern due to their acute or chronic poisoning and widespread use in agriculture around the world. There is a need for robust and field-deployable tools for onsite detection of OP pesticides in food and water. Herein, we present an integrated smartphone/resistive biosensor for simple, rapid, reagentless, and sensitive monitoring of OP pesticides in food and environmental water. The biosensor leverages the hydrolytic activity of acetylcholinesterase (AChE) to its substrate, acetylcholine (ACh), and unique transport properties of polyaniline nanofibers (PAnNFs) of chitosan/AChE/PAnNF/carbon nanotube (CNT) nanocomposite film on a gold interdigitated electrode. The principle of the sensor relies on OP inhibiting AChE, thus, reducing the rate of ACh hydrolysis and consequently decreasing the rate of protons doping the PAnNFs. Such resulted decrease in conductance of PAnNF can be used to quantify OP pesticides in a sample. A mobile app for the biosensor was developed for analyzing measurement data and displaying and sharing testing results. Under optimal conditions, the biosensor demonstrated a wide linear range (1 ppt–100 ppb) with a low detection limit (0.304 ppt) and high reproducibility (RSD <5%) for Paraoxon-Methyl (PM), a model analyte. Furthermore, the biosensor was successfully applied for analyzing PM spiked food/water samples with an average recovery rate of 98.3% and provided comparable results with liquid chromatography-mass spectrometry. As such, the nanosensing platform provides a promising tool for onsite rapid and sensitive detection of OP pesticides in food and environmental water.

Bidirectionally enhanced thermally conductive and mechanical properties MXene nanocomposite film via covalently bridged functionalized single-walled carbon nanotube

The development of thermal interface materials (TIMs) with excellent mechanical properties and efficient heat dissipation capability has become very necessary for the next generation of integrated electronics and flexible devices. Herein, a covalently cross-linked cellulose nanofiber/MXene/single-walled carbon nanotube (CNF/MXene/SWCNT-KH550, K-CMC) nanocomposite film was successfully fabricated by vacuum-assisted self-assembly method. This unique cross-linked ternary narce-like structure greatly promoted the load transfer and energy dissipation between the components, thereby improving the mechanical properties of K-CMC nanocomposite films. CNF/MXene/2wt%SWCNT-KH550(K-CMC2) nanocomposite film exhibits superior tensile strength of 255.1 MPa and satisfactory toughness of 3.9 MJ/m3. Additionally, strong covalent cross-linking network also effectively promotes the transfer of phonons between the components, notably in both vertical and horizontal directions. The K-CMC2 nanocomposite film exhibits in-plane thermal conductivity of 25.06 W m−1 K−1 and through-plane thermal conductivity of 1.64 W m−1 K−1, which enhanced 871% and 680% relative to the pure CNF film, respectively. The effective medium theory (EMT) proves that the formation of covalent cross-linked network effectively reduces the interfacial thermal resistance by 31.35%. These superior comprehensive properties endow the K-CMC nanocomposite films with great potential in the field of high power electronics.

Microwave Attenuation Studies of Polypyrrole-SWCNT Nanocomposite Films for Improved EMI Shielding

In the process of finding stable, lightweight, broadband, cost-effective and improved electromagnetic interference (EMI) shielding material, electromagnetic wave attenuation properties of polypyrrole (PPy)—single-walled carbon nanotube (SWCNT) nanocomposite hybrid films were investigated in X-band region (8.2–12.4 GHz) and reported in the present work. The incorporation of SWCNT as a nanofiller in polymer matrix exhibits enhanced EMI shielding performance as compared to pure polymer films. The substantial values of dielectric loss with good impedance matching contribute to improvement in EMI shielding performance. It is found that with an increase of SWCNT loading in polymer matrix from 0 wt% to 5 wt%, nanocomposite films display a gradual increase in AC conductivity and total shielding effectiveness. The maximum total shielding effectiveness of 32.10 dB and minimum reflection loss of −45.54 dB with a wide bandwidth of 3.1 GHz, were obtained for 5 wt% CNT loading. The present results revealed that the prepared nanocomposite films are appropriate materials for lightweight, broadband EMI shields for radar and stealth applications.

Conjugated Polymer /Multi Wall Carbon Nanotubes Composite Characterisation for Application in Volatile Organic Compounds Sensors

Polyimidazole multi-walled carbon nanotubes (MWCNTs) nanocomposite film were synthesised by chemical oxidation of imidazole monomer and addition of MWCNTs to the conductive polymer (CP) solution in 1:1 ratio. Chemical characterisation using FTIR where there is an increased in intensity of peaks in the control sample from 2823 and 2937 cm-1 to 2833 and 2947 cm-1 in Plm/MWCNTs composite respectively and Raman spectroscopy in which Plm/MWCNTs shows the so-called D-band (attributed to disordered sp2 and non-sp2 carbon defects in graphitic sheets) and G-band (attributed to the C–C vibration with the sp2 hybridized orbital in graphene structures) peaks at 1355 cm-1 and 1593 cm-1, but chemical analysis confirmed the mixing of the polymer and the MWCNTs. Electrical measurements using current voltammetry (CV) that shows a reversible wave that is the typical behavior of conductive surfaces in the presence of the redox couple and Impedance measurements in which the largest semicircle was obtained with Plm/CNTs film that corresponds to a film resistance on the real axis of 350 MΩ which is an indication of a higher electron transfer rate in the redox probe and good electrical behaviour. The overall results have shown that the composite has a significant electrical conductivity and can be applied in sensing volatile organic compounds in the environment.

Impact of CNT Concentrations on Structural, Morphological and Optical Properties of ZnO: CNT Nano composite Films

In this study, zinc oxide: carbon nanotube (ZnO: CNT) nano composite films with varying CNT concentrations (0,3,5,10, and 15) wt percent were generated utilizing the pulsed laser deposition (PLD) procedure on clean glass substrates at room temperature. The impact of CNT concentration on the structural, morphological, and optical features of ZnO: CNT nano thin films as deposited was examined. X-ray diffraction was used to evaluate the structure of the generated ZnO: CNT thin films, while an atomic force microscope was used to explore the morphological features of the nano films (AFM) and field emission scan electron microscopy (FESEM). The optical properties of prepared thin films were characterized and studied using UV-VIS-NIR spectrophotometer. The structures of prepared ZnO: CNT with different concentration of CNT thin films were polycrystalline. ZnO: CNT nano thin films were synthesized in hexagonal phase and the dominate orientation is (101). The crystallite sizes are 32 and 26 nm for (101) and (100)) planes for ZnO and ZnO: 15% CNT nano films respectively. These crystallite size are decreased with increasing CNT (0, 3,5,10 and 15) wt. %. The lowest grain size can be shown for ZnO, while the largest grain size can be seen in ZnO: CNT nano thin with 15% concentration, whereas FESEM micrographs displayed a typically rough, pronounced microstructure, with surface protrusions. The energy gap (Eg) of ZnO: CNT nano thin film with various concentrations is computed. The result analysis shows that Eg decreased with increasing CNT weight concentration. This type of behaviors make the prepared films are good candidate for broad range of applications such as optoelectronic and display devices.

Development of Cu/F-MWCNT/ZnO Based Active Layer for Long Term Soil Urea Measurements

There is a significant interest in the detection of nutrient levels in smart agriculture farms. In this paper, we report the development of Zinc oxide (ZnO) modified multi-walled Carbon nanotube (F-MWCNT) nanocomposite thin film layers specifically for soil nitrogenous fertilizers level detection. The nanostructured ZnO loaded over the surface of F-MWCNT forms the nanocomposite active layer. The surface morphology of the F-MWCNT/ZnO is characterized using field emission scanning electron microscopy (FeSEM) and energy-dispersive X-ray spectroscopy (EDS). Crystal phase and orientation of F-MWCNT, ZnO and F-MWCNT/ZnO nanocomposites were examined using an X-ray diffractometer (XRD). The electrochemical sensing characteristics of the Cu/F-MWCNT/ZnO structure was measured using an impedance/gain phase analyzing system and resulting composite structure was found to have a proportional impedance change with soil Urea levels. The performance of the sensor was investigated in the 1- 10 kHz range. The impedance magnitude was found to be a linearly decrease with the Urea levels.

Green technique solvent-free fabrication of silver nanoparticle–carbon nanotube flexible films for wearable sensors

Fabricating flexible/stretchable physical sensors has emerged as a topic of interest owing to the huge market demand for wearable medical devices and electronic skins for the regular and continuous monitoring of human health information. Herein, we report a green and efficient strategy for constructing a sensitive polydimethylsiloxane-derived wearable piezoresistive sensor, based on silver nanoparticle (AgNP)@multi-walled carbon nanotube (CNT) nanocomposite films. The developed sensing material exhibits good flexibility and electrical conductivity because of the interfacial effect between AgNPs and CNTs, leading to excellent sensing performances with good sensitivity, fast response time, low operating voltage, and mechanical stability, as measured under different pressure loading, bending angle, and percentage elongation conditions. In addition, finger movement recognition is sampled by testing the exceptional resistance change, and its practicality was further proven. Thus, the developed material has potential for application in wearable electronics. Notably, the entire sensor fabrication process is low-cost, environment-friendly, scalable, and industrially available, which is beneficial for industrial applications.

The Preparing and Characterization of Nanocomposite (PTh/SWCNT) for NO2 Gas Sensing

We prepared polythiophene (PTH) with single wall carbon nanotube (SWCNT) nanocomposite thin films for Nitrogen dioxide (NO2) gas sensing applications. Thin films were synthesized via electrochemical polymerization method onto (Indium tin oxide) ITO coated glass substrate of thiophene monomer with magnesium perchlorate and different concentration from SWCNT (0.012 and 0.016) % in the presence130mL of Acetonitrile used. X-ray diffraction (XRD), Field Emission Scanning Electron microscopy (FE-SEM), Atomic Force Microscope (AFM) and Fourier Transform Infrared Spectroscopy (FT-IR) were used to characterized these nanocomposite thin films. The response of these nanocomposite for NO2 gas was evaluated via monitoring the change time in presence 25% NO2 of with electrical resistance at (40, 80,120,160 and 200)°C. We can observe that the PTh/SWCNT films show a higher sensitivity as compare to pure PTH.

Polydimethylsiloxane/multi-walled carbon nanotube nanocomposite film prepared by ultrasonic-assisted forced impregnation with a superior photoacoustic conversion efficiency of 9.98 × 10−4

Polydimethylsiloxane/multi-walled carbon nanotube (PDMS/MWCNT) composite had high photoacoustic transduction efficiency owing to its high light absorption coefficient and low interfacial thermal resistance. The high expansion coefficient and light absorption ability of PDMS/MWCNT nanocomposite films have significant positive effects when it is used as a laser ultrasonic transducer. We introduce an ultrasonic-assisted forced impregnation method for the preparation of PDMS/MWCNT nanocomposite films. PDMS was used as the matrix phase, and MWCNTs were used as the nano-supporting framework. PDMS matrix was introduced into the MWCNT framework by the forced impregnation method. The morphology, thermal, and mechanical properties of the nanocomposite film were analyzed systematically. The photoacoustic conversion efficiency was researched through both experiment and simulation methods. The output sound pressure of our PDMS/MWCNT nanocomposite film reached 7.59 MPa when applied as an ultrasonic transducer under the pulsed laser excitation of 1 mJ / pulse energy. The photoacoustic conversion efficiency of our sample was 9.98 × 10 − 4, three times higher than similar products reported before, which offered the possibility to greatly enhance the photoacoustic signals.

Mechanical and Functional Properties of Novel Biobased Poly(decylene-2,5-furanoate)/Carbon Nanotubes Nanocomposite Films.

The present work investigates the microstructural, thermo-mechanical, and electrical properties of a promising, but still not thoroughly studied, biobased polymer, i.e., poly(decylene furanoate) (PDeF), and its performance when multi-walled carbon nanotubes (CNTs) are added. After sample preparation by solution mixing and film casting, the microstructural investigation evidences that the fracture surface becomes smoother and more homogeneous with a small fraction of CNTs, and that the production process is suitable to achieve good disentanglement and dispersion of CNTs within the matrix, although some aggregates are still observable. CNTs act as nucleating agents for PDeF crystals, as evidenced by differential scanning calorimetry, as the crystallinity degree increases from 43.2% of neat PDeF to 55.0% with a CNT content of 2 phr, while the crystallization temperature increases from 68.4 °C of PDeF to 91.7 °C of PDeF-CNT-2. A similar trend in crystallinity is confirmed by X-ray diffraction, after detailed Rietveld analysis with a three-phase model. CNTs also remarkably improve the mechanical performance of the bioderived polymer, as the elastic modulus increases up to 123% and the stress at break up to 131%. The strain at break also increases by +71% when a small amount of 0.25 phr of CNTs are added, which is probably the consequence of a more homogeneous microstructure. The long-term mechanical performance is also improved upon CNT addition, as the creep compliance decreases considerably, which was observed for both the elastic and the viscoelastic component. Finally, the films become electrically dissipative for a CNT content of 1 phr and conductive for a CNT amount of 2 phr. This study contributes to highlight the properties of bioderived furan-based polymer PDeF and evidences the potential of CNTs as a promising nanofiller for this matrix.

Improved flame-retardant properties of polydimethylsiloxane/multi-walled carbon nanotube nanocomposites

The flame-retardant properties of polydimethylsiloxane (PDMS)/oxidised multi-walled carbon nanotubes (MWCNT–COOH) nanocomposite films were dispersed using a nonionic acrylate copolymer surfactant. The nanocomposite films were prepared by spin coating and characterised using SEM, quasi-elastic cold-neutron scattering, TGA–FTIR, cone calorimetry, and LOI. The PDMS/surfactant/MWCNT–COOH (PSM) nanocomposite displayed superior flame-retardant performance compared to materials containing only surfactant or MWCNT–COOH. The peak heat release rate, the peak smoke production rate, total smoke release rate, carbon monoxide, and carbon dioxide production from PSM were 42, 47, 18, 28, and 47% less than the PDMS control. The LOI results for PSM exhibited a value of 32% with respect to 25% for the PDMS. PSM suppresses the smoke emission and inhibits penetration of the air reacting with the gas volatiles of the material. These new nanocomposites provide a valuable improvement in flame-retardant capabilities by physical barrier effect compared to other PDMS polymer materials.

Effect of nature of polymer as a binder in making photoanode layer and its influence on the efficiency of dye-sensitized solar cells

A simple method has been developed for the preparation of photoanode paste from hydrothermally synthesized nanocomposite, using different nature of polymers viz., synthetic: poly(vinyl alcohol) and polystyrene (PS) and natural: casein and sodium alginate (NaAlg) as binders. The titanium dioxide (TiO2)/multi-walled carbon nanotube (MWCNT) nanocomposite powder and film were characterized for analysis of their structure, crystallinity and morphology by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopy. Dye-sensitized solar cells (DSSCs) were fabricated using TiO2/MWCNT composite paste made with different binders as photoanode, N719 dye, platinum as photocathode and Idolyte HI-30. The observed results of photocurrent density–voltage characteristics and electrochemical impedance spectroscopy suggested that the nature of the binder used in making photoanode film showed significant influence on the overall characteristics of DSSCs. Among the cells fabricated, the DSSC fabricated using TiO2/MWCNT-PS binder showed highest power conversion efficiency of 3.03%.

Synthesis and characterization of platinum multi-walled carbon nanotubes nanocomposite film electrode

Carbon nanotubes (CNTs) were synthesized by a bimetallic (Fe–Co/CaCO3) catalytic chemical vapour deposition (CCVD) method. The synthesized CNTs were purified with acid to remove the catalyst impurities to enhance the deposition of platinum (Pt) onto the CNTs surface. Platinum multiwall (Pt-MWCNTs) nanocomposites were produced by a wet impregnation technique dispersed in Texanol and Acrylic resins to form a paste. The paste was screen printed on an FTO glass substrate. Surface morphology, microstructure, chemical composition, crystallographic phase, surface area and electrical performance of the Pt-MWCNTs nanocomposites were measured by HRSEM, HRTEM, EDS, XPS and XRD. The electrical conductivity of the electrode produced was found to be 4.927 S m−1. The results showed that the prepared nanocomposites will be a good electrode material in solar cell applications.

Characterization of PVC/MWCNTs Nanocomposite: Solvent Blend

Abstract Polyvinyl Vinyl Chloride (PVC) multiwall carbon nanotubes (MWCNTs) nanocomposite flexible films were prepared using the solvent blend technique. Chloroform (CHCl3) and tetrahydrofuran ((CH2)4O) were used as solvents for MWCNTs and PVC, respectively. The effect of the solvents’ blend on electrical, optical and thermal properties of PVC/MWCNTs were investigated. The results of the Raman spectrum showed that all the characteristic bands of PVC polymer have a slight shift due to addition of MWCNTs. Electrical results showed that the nanocomposite samples with chloroform volume ratios of 10% and 25% had nearly the same conductivity. This is attributed to the formation of the MWCNTs network, which assisted in electrical conductivity. The I-V hysteresis curve decreases as the temperature increases and as it approaches the glass transition temperature. The non-isothermal kinetics analysis for PVC and PVC/MWCNTs were investigated by Thermogravimetry Analysis (TGA) using the model-free kinetic method. The non-isothermal measurements were carried out at five heating rates of 5 to 40∘C/min. The results show that the main decomposition process has constant apparent activation energies for all samples. The use of the bi-solvent method has improved the dispersion of untreated MWCNTs, and this has been reflected on the stability of both electrical and thermal properties.

Enhanced Thermoelectric Performance of Conjugated Polymer/CNT Nanocomposites by Modulating the Potential Barrier Difference between Conjugated Polymer and CNT

Small-bundled single-walled carbon nanotube (SSWCNT) nanocomposite films with two different conjugated polymers were facilely prepared by using a micronizing mill. The influence of the difference i...

Development of bio-hybrid piezoresistive nanocomposites using silk-elastin protein copolymers

Recombinant silk-elastin-like protein (SELP)/carbon nanotubes (CNTs) nanocomposite films with different amounts of CNTs (1, 3 and 6 wt%) were prepared by solvent casting. The produced films were stabilized by exposure to methanol that induces an increase of the β-structure content. The CNTs were homogeneously distributed into the SELP matrix and did not induce significant alterations into its chemical structure. The incorporation of CNTs also increased the thermal stability of the films. Further, the incorporation of 1 wt% of CNTs greatly improved the mechanical properties of the SELP matrix leading to a 6-fold increase in strain-to-failure and to increase the ultimate tensile strength with minor differences in modulus of elasticity. The nanocomposites exhibited a good linearity between deformation and electrical resistance variation with electrical conductivity increasing with the nanofiller content up to 0.8 S m−1. Finally, the produced nanocomposites were non-cytotoxic indicating their suitability for biomedical applications.

PANI/MWCNT based humidity sensor

Polyaniline Multi wall Carbon nanotube (PANI/MWCNTs) nanocomposite thin films have been prepared by Plasma jet polymerization at low frequency on glass substrate with preliminary deposited aluminum electrodes to form Al/PANI-MWCNT/Al surface-type capacitive humidity sensors, the gap between the electrodes about 50 μm and the MWCNTs weight concentration varied between 0, 1, 2, 3, 4%. The diameter of the MWCNTs was in the range of 8-15 nm and the length 10-55 μm. The capacitance-humidity relationships of the sensors were investigated at humidity levels from 35 to 90% RH. The electrical properties showed that the capacity increased with increasing relative humidity, and that the sensitivity of the sensor increases with the increase of the additive (MWCNTs); while each of the response time and the recovery time increasing with concentration. The change in MWCNTs concentration leads to a change in the energy gap as well as the initial capacity. The capacitance increases linearly with the relative humidity at MWCNTs concentration of 3% for thus the possibility of manufacturing humidity sensor with good specifications at this concentration.