35 research outputs found
Integration of a Carbon Nanotube Network on a Microelectromechanical Switch for Ultralong Contact Lifetime
No full textMicro-/nanoelectromechanical (MEM/NEM) switches have been extensively studied to address the limitations of transistors, such as the increased standby power consumption and performance dependence on temperature and radiation. However, their lifetimes are limited owing to the degradation of the contact surfaces. Even though several materials and structural designs have been recently developed to improve the lifetime, the production of a microswitch that is compatible with a complementary metal-oxide semiconductor (CMOS) with a long lifetime remains a significant challenge. We demonstrate a vertically actuated MEM switch with extremely high reliability by integrating a carbon nanotube (CNT) network on a gold electrode as the contact material using a low-temperature, CMOS-compatible solution process. In addition to their outstanding mechanical and electrical properties of CNTs, their deformability dramatically increases the effective contact area of the switch, thus resulting in the extension of the lifetime. The CNT-coated MEM switch exhibits a lifetime that is more than 7 x 10(8) cycles when operated in hot-switching conditions, which is 1.9 x 10(4) times longer than that of a control device without CNTs. The switch also shows an excellent switching performance, including a low electrical resistance, high on/off ratio, and an extremely small off-state current.
Fabrication of C-doped WO<inf>3</inf> nanoamterial-based gas sensors for highly sensitive NO<inf>2</inf> detection at room temperature
No full textLow-voltage and low-power field-ionization gas sensor based on micro-gap between suspended silver nanowires electrodes for toluene detection
No full textFlexible, Transparent, Sensitive, and Crosstalk-Free Capacitive Tactile Sensor Array Based on Graphene Electrodes and Air Dielectric
No full textSensors: Flexible, Transparent, Sensitive, and Crosstalk-Free Capacitive Tactile Sensor Array Based on Graphene Electrodes and Air Dielectric (Adv. Electron. Mater. 1/2018)
No full textMulti‐Layered, Hierarchical Fabric‐Based Tactile Sensors with High Sensitivity and Linearity in Ultrawide Pressure Range
No full textInteractive Haptic System with Multimodal Tactile Sensing and Hydraulic Feedback for Realistic Human–Machine Interaction
No full textWith the increasing demand for immersive haptic experiences, multimodal tactile sensing and feedback have become crucial for enhancing user interaction. In this work, an interactive haptic system comprising a robotic hand and wearable tactile feedback device is introduced to facilitate tactile information exchange between humans and robots. The robotic hand, equipped with force and temperature sensors, mimics human movements through vision recognition and captures detailed tactile data. The data are then transmitted to the user through a hydraulic feedback device, providing realistic touch sensations. The dual capabilities of the hydraulic mechanism to simultaneously simulate both pressure and temperature sensations simplify the device structure and enhance reliability compared to systems that require multiple tactile actuators. The force feedback system delivers pressures ranging from 0.5 to 10.5 N across five levels while the temperature feedback mechanism provides thermal sensations ranging from 3 to 50 °C across three levels. Extensive experimental validations demonstrate the system's effectiveness in applications such as remote robotic surgery and telepresence, enabling users to perceive real‐time contact pressure and temperature during remote manipulation tasks. The proposed system, capable of delivering multimodal tactile feedback through a single actuator, represents a significant step toward more immersive and realistic haptic experiences, highlighting its broad applicability
Flexible and transparent NO<inf>2</inf> sensor using functionalized MoS<inf>2</inf> with light-enhanced response
No full textA highly sensitive and stretchable PVA-based hydrogel strain sensor with facile acrylic elastomer encapsulation
No full textAbstract Hydrogel-based strain sensors are highly promising for wearable electronics; however, their practical application is often limited by their low sensitivity and tendency to dehydrate. This paper reports on the development of a high-performance strain sensor that addresses these limitations simultaneously through a synergistic material and structural design. A conductive hydrogel composed of a polyvinyl alcohol matrix, multiwalled carbon nanotube filler, and borax cross-linker is encapsulated using a simple and effective lamination process with a self-adhesive, transparent acrylic elastomer film. This facile encapsulation method provides a robust hermetic seal that ensures environmental stability without compromising device flexibility. The resulting device exhibits a remarkable gauge factor of approximately 172 in the high-strain regime (30–100%), negligible signal drift, and stable performance over prolonged cyclic loading. Furthermore, the encapsulated sensor maintains durability and reliable adhesion under humid or saline conditions, validating its suitability for wearable use. The combination of superior sensitivity, long-term stability, and a scalable, low-temperature fabrication process establishes this work as a practical route toward robust hydrogel-based sensors for soft robotics and human-motion monitoring
Fabrication and characterization of VOC sensor array based on SnO2 and ZnO nanoparticles functionalized by metalloporphyrins
No full textAbstract A volatile organic compound (VOC) sensor array based on metal oxide nanoparticles (MOX NPs) functionalized by metalloporphyrins (MPPs) was demonstrated. The VOC sensor array was composed of four single sensors based on SnO2 NPs/cobalt-porphyrin, SnO2 NPs/zinc-porphyrin, SnO2 NPs/nickel-porphyrin and ZnO NPs/cobalt-porphyrin. The MOX NP/MPP-based sensors were fabricated by drop-casting the MOX NPs dispersion and MPPs solution onto a MEMS platform. The fabricated sensor successfully detected toluene at a concentration as low as 20 ppb, which is below the limit detection concentration of previously reported porphyrin-based VOC sensor arrays. We also confirmed the selectivity between benzene, toluene, ethylbenzene, and xylene (BTEX) by using principal component analysis in contrast to previous studies on MOX/MPP-based sensor. BTEX was classified from 1 to 9 ppm at a resolution of 2 ppm, and the sensor array showed stable performance even after considerable impact
