MXene is widely used for electrode materials. However, the interfacial resistance between metal and semiconductor affects the device performance. The strain has become an effective strategy to improve interfacial properties. With the aim of revealing the interface mechanism and improving device performance, we use the first-principles calculation to investigate the electronic properties of Ti 3 C 2 T 2 /MoS 2 (T = F, O, OH) junctions and the effect of strain on the interfaces. The calculations show weak forces between Ti 3 C 2 T 2 and MoS 2 monolayer, and the interfacial interaction decreases in the order of Ti 3 C 2 (OH)

piezoelectricity, [21,22] and turboelectricity. [23,24] Among them, the resistivetype soft sensor is particularly prominent for its flexibility, stretchability, and simple support system. [1,[16][17][18] Resistive-type soft sensors normally consist of a conductive sensor film and a soft substrate. [1] Polydimethylsiloxane (PDMS) has become prevalent in using as flexible and stretchable substrate owing to its remarkable elasticity, simple processing, high thermal stability, and chemical inertness. [1][2][3]7,12,25] The most essential issue of strain sensor is the choice of sensitive material. Carbon nanotube (CNT) has been broadly used in strain sensors due to its excellent mechanical properties, chemical inertness, and low cost, [1,2,5,6,10] whose stretchability could reached 280% [7] or even 500%. [11] In order to make up some defects that carbon base materials often suffered, like low conductivity (sheet resistance of ≈4 kΩ sq −1 [5] ) and the relatively low sensitivity, [9,11] researchers has mixed CNT with metal materials. Takei and some researchers have mixed CNT with silver particles physically, [13] while Zhang and others using chemical methods produced AgNP modified CNTs. [26] Metal materials have good electrical properties [1,2,7,8,15] and high sensitivity (GF is easily achieved twice or even more times than CNTs [7,12] ), and can effectively supplement the shortage of CNT. Based on our previous researches, Ag@CNT synthesized by chemical reduction is a good material that combines the both advantages of CNTs and silver nanoparticles. [25] However, there are still some drawbacks here: pristine CNTs are insoluble in water or organic solvents and easily agglomerate; the bond between CNT and metal nanoparticle is not as tight and strong. On this basis, how to further improve the performance of Ag@CNT is an important and meaningful research direction. Researches on this aspect have not been reported as far as we know.In this study, we fabricated a stretchable and flexible strain sensor using Ag@COOH functionalized CNT. To get a better performance, three different CNTs were chosen for comparison: pristine CNT, COOH functionalized CNT, and OH functionalized CNT. In order to deeply compare the mechanism of binding energy and charge transfer ability, different Combining metal and carbon nanomaterials is an effective way to significantly enhance the performance of soft strain sensors. The role of carbon nanotubes (CNTs) functionalized with different chemical groups in improving the properties of nanosilver-coated carbon nanotubes (Ag@CNT) is investigated. The functionalized CNTs are first calculated with different chemical groups combined with the silver atoms. Ag@COOH-functionalized CNTs exhibit greater binding energy and a smaller bandgap, which leads to better hydrophilicity, stability, and stronger bonding. Ag@CNTs are then synthesized using pristine CNT, OH-functionalized CNT, and COOHfunctionalized CNT. Strain sensors are fabricated by wrapping the sensing material with polydimethylsiloxane (PDMS) to form a s...

We fabricated a flexible sensing system, including the preparation of sensors and construction of the signal processing computing platform, which enabled human health monitoring by collecting pulse signals.

Recently, highly stretchable strain sensors have attracted considerable attention. Identifying alternatives to sensitive unit materials and flexible substrates is critical in the fabrication of sensors.

The efficient preparation of energy harvesters plays a pivotal role in large‐scale applications, especially in complex or smart electronics. Currently, most of home‐made laboratorial electrical devices are fabricated by handcraft, which severely suppresses the development of triboelectric nanogenerators (TENGs). Herein, a fully 3D‐printing TENG is reported, with a PDMS tribolayer and frame directly printed on an Al electrode. The one‐step fabrication not only simplifies the manufacturing process, but also narrows differences between devices and realizes large‐scale production. The subtly fabricated TENG shows a high sensitivity to microvibration, resulting in that a voiceprint recognition sensor is demonstrated to detect human language. Because of the ingenious 3D‐printing technique, the TENG sensor can identify human words steadily and accurately. Herein, a way is paved in larger‐scale applications based on TENGs and implies more potential in artificial intelligence and future robots.

The wide application prospects of flexible strain sensors and pressure sensors in robotic perception have led to an urgent demand for the high‐precision customized manufacturing and flexible integration of such devices. Herein, a 3D‐printed wearable strain and tactile sensing array is developed for robotic perception by integrating a flexible strain sensor and a pressure sensor with porous structures. The flexible strain sensor has a wide linear measurement range of 67.5% with a sensitivity of 2.64. Meanwhile, the flexible pressure sensor has a continuous pressure‐monitoring ability in the range of 0–1 N, and it is particularly sensitive to small pressures within 0.2 N. Both the sensors provide a stable output for the seamless sensing of different stimuli, and devices from the same batch provide highly consistent responses. By fully exploiting the flexibility of digital light‐processing 3D printing, the sensing array is customized for a robotic hand to realize the grip and finger bending perceptions of the manipulator.

The adsorption of dinitrogen in the presence of dihydrogen over supported rhodium catalyst films has been studied at pressures up to 8000 Torr using infrared spectroscopy as the analytical probe. The integrated area of the Rh-N2 band at 2248-2258 cm-' has been employed to estimate coverages and adsorption equilibrium constants as a function of temperature. These data were used to determine enthalpies and entropies of adsorption for the Rh-Nz species. It was found that the presence of Rh-H species coadsorbed with the Rh-N2 species caused intensity enhancement of the Rh-N2 infrared band, a blue shift in its frequency, increased coverage of NZ relative to a Rh-H-free surface, and a stronger interaction of N2 with Rh. Two forms of hydrogen interacting with Rh appear to be important in causing these observations-a weakly-bound reversible form with a Rh-H infrared band at 2013 cm-' and a strongly-bound form postulated by others which has no detectable infrared band. It was also observed that the support Ti02 induced stronger N2 interaction with Rh than did A1203; the trend referred to above concerning coadsorbed Rh-H was observed for both supports.

Flexible pressure sensors based on capacitive induction have become a research hot-spot because of low energy consumption and excellent performance in recent years. In practical applications, a wide range of detection and low-cost mass-produced flexible pressure sensors are ideal. Herein, this paper presents a wide detection range capacitive pressure sensor based on a structured elastic electrode, which is low cost and can be mass-produced by a simple method of micropore PE tape molding. Test results show that the sensor's pressure detection range is 0-45 kPa. This is because the upper structure of the capacitive sensor is constantly changing when subjected to different external pressures, so that the contact area of the upper substrate of the sensor becomes larger and the distance between the upper and lower substrates becomes smaller. In addition, this capacitive pressure sensor exhibits low detection limit (<300 Pa), ultra-short response time (<50 ms) and high operational stability for repeated loading/unloading pressure cycles. The sensor owns excellent resolution and can distinguish language, and the sensor can be used to monitor pulse. Low-cost mass production and wide detection range of flexible capacitive pressure sensors lay the foundation for the development of electronic skin, contact inspection applications and wearable healthcare monitors.