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Carbon nanotube (CNT) fibers are used in various applications, such as electrical cables, supercapacitors, physical sensors, artificial muscles, and electronic devices, due to their excellent mechanical, thermal, and electrical properties. Herein, the orientation-dependent electrical characteristics of a CNT fiber array were investigated. A force resistive sensor with good sensitivity and reliable operation was developed using the array and integrated with a real-time data storage and wireless monitoring system. In addition, a CNT fiber-based position sensor was developed for application in smart fabrics. This study introduces an easy-to-manufacture, low-cost, robust CNT fiber-based sensing platform that can be used with an open-source microcontroller for integration with the Internet of things. [ABSTRACT FROM AUTHOR]

Fiber‐shaped supercapacitors (FSSCs) are the most state‐of‐the‐art power supplies suitable for wearable devices, but the intrinsically limited cylindrical space of fibers restricts their high electrochemical performance, which must be overcome with a delicate and systematic architectural process. Here, a simple but effective 3D architectural strategy for fabricating FSSCs with high performance and flexibility is proposed. Highly conductive liquid crystal spun carbon nanotube fiber (CNTF) is an excellent 1D core fiber for the electrophoretic deposition of graphene oxide (GO). The deposited GO forms a vertical 3D structure on the CNTF (VG@CNTF), which can be successfully preserved by a consecutive coating of pseudocapacitive active materials onto the surface of VG. Notably, a solid‐state asymmetric FSSC shows an outstanding performance of 65 Wh kg−1 at 100 kW kg−1 and exceptional stability and flexibility (capacitance retention of 98.60% at bending angles of 90° and 93.1% after 5000 bending cycles). This work can provide new insight into the development of high‐performance FSSCs for practical wearable applications. [ABSTRACT FROM AUTHOR]

Static and low frequency noise (LFN) characterizations in two-dimensional (2D) N-type random network thin film transistors (RN-TFTs) based on single-walled carbon nanotubes were presented. For the electrical parameter extraction, the Y-function method was used to suppress the series resistance (Rsd) influence. The gate-to-channel capacitance (Cgc) was directly measured by the split capacitance-to-voltage method and compared to 2D metal-plate capacitance model (C2D). In addition, to account for the percolation-dominated 2D RN-TFTs, a numerical percolation simulation was performed. LFN measurements were also carried out and the results were well interpreted by the carrier number and correlated mobility fluctuation model. Finally, one-dimensional (1D) cylindrical analytical capacitance based model (C1D) was suggested and applied to provide better consistency between all electrical parameters based on experimental and simulation results. [ABSTRACT FROM AUTHOR]

Advanced physical sensors based on carbon nanotube/polydimethylsiloxane (CNT/PDMS) nanocomposites have recently attracted much attention for potential applications such as wearable and flexible electronic devices. In this work, a CNT/PDMS sponge was fabricated and their capacitive as well as resistive response was investigated by impedance characterization with an equivalent circuit model. The newly defined gauge factor, which considers simultaneously both the piezocapacitive and piezoresistive effects of CNT/PDMS sponge sensors, showed a significantly improved sensitivity. This work provides important information for a better understanding of CNT/PDMS nanocomposites and their sensing performance. [ABSTRACT FROM AUTHOR]

In this article, we demonstrate the potential of solution-processed boron nitride (BN) thin films for high performance single-walled carbon nanotube thin-film transistors (SWCNT-TFTs) with low-voltage operation. The use of BN thin films between solution-processed high-k dielectric layers improved the interfacial characteristics of metal-insulator-metal devices, thereby reducing the current density by three orders of magnitude. We also investigated the origin of improved device performance in SWCNT-TFTs by employing solution-processed BN thin films as an encapsulation layer. The BN encapsulation layer improves the electrical characteristics of SWCNT-TFTs, which includes the device key metrics of linear field-effect mobility, sub-threshold swing, and threshold voltage as well as the long-term stability against the aging effect in air. Such improvements can be achieved by reduced interaction of interfacial localized states with charge carriers. We believe that this work can open up a promising route to demonstrate the potential of solution-processed BN thin films on nanoelectronics. [ABSTRACT FROM AUTHOR]

We demonstrate high-performance single-walled carbon nanotube thin-film transistors (SWCNT-TFTs) using the simple and robust method of an interacting fluoropolymer encapsulation with thermal annealing in vacuum to reduce the charge transfer. With an optimized combination of the fabrication process and the device configuration, drop-casted SWCNT-TFTs exhibit a field-effect mobility of \sim 18 cm2/ \text{V}\,\cdot \, \text{s} in the linear regime, an ON–OFF-current ratio of \sim 10^{6}$ , a threshold voltage of around 0 V, and a subthreshold swing of 97 mV/decade, which is among the best results that have been achieved in 2-D random networks of the SWCNTs. We also investigate the instability characteristics in the SWCNT-TFTs encapsulated with fluoropolymer during the prolonged electrical bias-stress. Interestingly, the drop in drain current of the SWCNT-TFTs was partially recovered with a second phenomenon that increases the drain current after a certain time. The hydrophobic surface that the fluoropolymer film possesses, reduced the chemical interaction of charge carriers with the hydroxyl (–OH) functional groups which act as defects in the SWCNT-TFTs. [ABSTRACT FROM AUTHOR]

• Aligned multi-walled (MW) carbon nanotube-coated yarn (CNT-CY) arrays were obtained from a simple dipping-and-drying method. • Piezoresistive force and bending sensors with good performance were fabricated by using MWCNT-CY. • Verification was performed using a proof-of-concept force sensor matrix with an Arduino open-source microcontroller. • A force sensor combined with real-time data storage in Google Cloud was also successfully demonstrated. [Display omitted] Advanced sensors based on the Internet of Things (IoT) are bringing new technology and productivity paradigms to the era of the fourth industrial revolution. Here, piezoresistive force and bending sensors with good performance (sensitivity ≈ 0.3 kPa−1 and ∆normalized resistance/∆curvature ≈1.5 cm) were fabricated by using perpendicularly aligned multi-walled (MW) carbon nanotube-coated yarn (CNT-CY) arrays, which were obtained from a simple dipping-and-drying method. Verification was performed using a proof-of-concept force sensor matrix with an Arduino open-source microcontroller. In addition, a force sensor combined with real-time data storage in Google Cloud was successfully demonstrated. This work provides important information for the development of a robust, low-cost, and easy-to-manufacture IoT platform with MWCNT-based composites as an active sensing material. [ABSTRACT FROM AUTHOR]

This letter reports a strong yellow emission of Y3Al5O12:Ce3+ (YAG:Ce) mixed with ZnS:Ag,Cl under electron excitation. The penetration depths of electron of 1 keV and photon of 2.7 eV in YAG:Ce were estimated to be approximately 1450 Å and 4.65 mm, respectively. Deeper penetration of blue light from ZnS:Ag,Cl helps to excite a larger number of Ce3+ in a mixture (ZnS:Ag,Cl+YAG:Ce), and YAG:Ce showed strong yellow emission via both cathodoluminescence and photoluminescence. The mixture showed the brightness of 120.5% compared to R,G,B phosphor mixture. This mixture of two phosphors was applied to a carbon nanotube field emission backlight unit. [ABSTRACT FROM AUTHOR]

• Flexible chemiresistive pH sensors based on printed nanocomposites of SWCNTs and Nafion are demonstrated. • The operational stability of flexible pH sensors is investigated by performing bending tests. • A real-time pH sensor system integrated into a drone application for monitoring water quality is demonstrated. High-performance flexible pH sensors based on nanocomposites of single-wall carbon nanotubes (SWCNTs) and Nafion, fabricated by screen printing on flexible substrates in ambient air are demonstrated. The electrical characteristics and thus the sensing performance of the pH sensors monitoring the change in resistance of printed nanocomposite films in a wide range of pH from 1 to 12 were controlled by the number of printed layers in multi-patterns. The operational stability of the flexible pH sensors was nearly unchanged after 200 cycles of bending tests having a curvature radius of 5 mm, which is essential for intergration of flexible pH sensors into wearable nanoelectronics. The sensing mechanism of the chemiresistive pH sensors based on nanocomposites is investigated in terms of chemical reaction. The hydrogen or hydroxide ions in the pH solution interact with the carbonyl and C H bonds bonds of the nanocomposite film, which induces or withdraws positively charged carriers, respectively. In addition, a real-time pH sensor system integrated into a drone application with wireless communication and data transmitting modules is demonstrated for the simultaneous visualization of processed data and remote detection of targets on the user's smartphone based on a designed Android algorithm. [ABSTRACT FROM AUTHOR]

Cylindrical fullerenes (or carbon nanotubes (CNTs)) have been extensively investigated as potential sensor platforms due to effective and practical manipulation of their physical and chemical properties by functionalization/doping with chemical groups suitable for novel nanocarrier systems. CNTs play a significant role in biomedical applications due to rapid development of synthetic methods, structural integration, surface area-controlled heteroatom doping, and electrical conductivity. This review article comprehensively summarized recent trends in biomedical science and technologies utilizing a promising nanomaterial of CNTs in disease diagnosis and therapeutics, based on their biocompatibility and significance in drug delivery, implants, and bio imaging. Biocompatibility of CNTs is essential for designing effective and practical electronic applications in the biomedical field particularly due to their growing potential in the delivery of anticancer agents. Furthermore, functionalized CNTs have been shown to exhibit advanced electrochemical properties, responsible for functioning of numerous oxidase and dehydrogenase based amperometric biosensors. Finally, faster signal transduction by CNTs allows charge transfer between underlying electrode and redox centres of biomolecules (enzymes). Image 1 • Carbon nanotubes (CNTs) used as nanocarriers are promising for diverse biomedical applications. • CNTs are effective and practical in delivery of anticancer agents due to their nano dimensions and biocompatibility. • CNTs have been investigated for multifunctional nano-probes with large scattering cross-section for biomedical imaging. [ABSTRACT FROM AUTHOR]

In this study, carbon nanotube fibers (CNTFs) were strengthened by densifying and reorienting CNT bundles using a triblock copolymer (poly (propylene glycol)– block -poly (ethylene glycol)– block -poly (propylene glycol (PPG–PEG–PPG)). This copolymer possesses a unique combination of hydrophilic and hydrophobic molecules, enabling it to easily penetrate and expand the distance between bundles. Through a stretching process after impregnation, the CNTFs induced a structural alignment of the bundles, resulting in high integration of the CNT bundles. The microstructural analysis of the fiber cross-section revealed an increased number of aligned CNTs along the fiber direction, concomitant with a reduction in the bundle-to-bundle distance owing to bundle aggregation. The highly aligned structure showed an average specific tensile strength of 0.536 N/tex and specific elastic modulus of 66.3 N/tex, which is an increase of 175 % and 252 %, respectively, compared to the pristine CNTF. The polymer infiltration stretching method effectively aggregated CNT bundles and removed macro voids within the CNTF. Additionally, the densification and alignment of CNTFs were characterized through novel low-frequency noise measurement and analysis. Understanding the nanoscale structure and morphology of CNTFs in nanoscale will provide valuable guidance for building enhanced strengthening strategies. [Display omitted] • CNT fiber (CNTF) was reoriented and densified by wet stretching method using a triblock copolymer. • The structure modified CNTFs enhanced tensile strength, Young's modulus, and electrical conductivities. • A low-frequency noise method was used to investigate the densification and alignment quality of CNT bundles. [ABSTRACT FROM AUTHOR]

The global concern of electronic waste (e-waste) relevant to the negative impact on the environment and ecological systems have been attracted extensive attention to the imminent solution to the development of sustainable electronic devices. To deal with that, we propose renewable soybean oil to produce thermoset films, serving them as flexible green substrates for the ion-gated transistor (IGT). The effective adjustment of dielectric property and flexibility by controlling the amount of ionic moieties source gifted the thermoset with an excellent sensitivity of 8.75 × 10−3 kPa−1 while the detection limitations up to 20 kPa. Furthermore, the all-carbon-component IGT based on soybean substrate also realized with the best electrical performance of I on /width of 0.52 μA/mm, and >250 of an on/off ratio and 2.6 μA of on-current at a low voltage operation of V DS = −0.5 V. The soybean oil-based substrate showed fast decomposition in a mildly basic solution, with the graphene electrode recapture efficiency being higher than 95% for the remaking of new transistors. The excellent working performance in both manners of the touch sensor and the field effect transistor accompanied by the highly green fabrication technology clues the high potential in the next-generation electronics that require a significant level of sustainability. [Display omitted] • Green soybean oil-based substrates were prepared through thiol-ene reaction. • The incorporated ionic moieties boosted dielectrics and flexibility of the substrates. • IGT based on natural source substrates showed high I on/off at low voltage operating. • An excellent sensitivity of 8.75 × 10−3 kPa−1 was achieved for force sensing. • The substrates showed fast decomposition in a mild basic solution. [ABSTRACT FROM AUTHOR]