No abstract

No abstract

No abstract

Flexible conductive materials and flexible electronic devices are driving the development of the next generation of cutting‐edge wearable electronics. However, the existing hydrogel‐based flexible conductive materials have limited tensile capacity, low toughness, and poor anti‐fatigue performance, resulting in narrow sensing area and insufficient durability. In this paper, a conductive nanocomposite hydrogel with high ductility, toughness, and fatigue resistance is prepared by combining silver coated copper (Ag@Cu) nanoparticles with gelatin followed by one‐step immersion in sodium sulfate (Na2SO4) solution. The salting‐out of gelatin in Na2SO4 solution greatly improve the mechanical properties of this gelatin‐based hydrogel. The uniform distribution of Ag@Cu nanoparticles inside the whole hydrogel endow the composite hydrogel with excellent electrical conductivity (1.35 S m−1). In addition, it displayed high and stable tensile strain sensitivity over a wide strain range (gauge factor = 2.08). Therefore, the Ag@Cu‐Gel hydrogel is sensitive and stable enough to be successfully utilized as flexible wearable sensor for detecting human motion signals in real time, such as bending of human joints, swallowing, and throat vocalization. Furthermore, this hydrogel is also suitable for application as electronic skin for bionic robots. The above results demonstrate the promising application of Ag@Cu‐Gel hydrogel for wearable electronics.

No abstract

No abstract

Flexible and wearable strain sensors have received extensive attention in the preparation of human−machine interface equipment, intelligent robots, and personalized health-monitoring biosensors. However, it has been a formidable challenge to develop materials with satisfying stretchability, sharp and quick sensitivity, and good linearity. Herein, we report a multifunctional nanocomposite hydrogel with outstanding stretchability, fatigue resistance, and electrical conductivity by adding Ag nanoparticle-coated graphene oxide (Ag/TA@GO)-based nanocomplexes into a polyacrylamide (PAM) hydrogel matrix. This Ag/TA@GO-PAM nanocomposite hydrogel shows an ultrahigh stretchability of 1250% and excellent conductivity (0.15 S•m −1 ). The sensitivity is improved to GF = 3.1; meanwhile, the preeminent linear sensing property is achieved in the ultrawide strain range of 0 to 1000%, with a high R 2 value of 0.994. Moreover, when the Ag/TA@GO-PAM hydrogel is assembled into a wearable strain sensor with a sandwiched structure, it can detect large and delicate motions (for example, facial expression and pronunciation), with excellent sensitivity and durability. In addition, the nanocomposite hydrogel is further explored from practical aspects for circuit assembly and repair, E-skin of bionic robots, and information encryption. Therefore, this study provides a basis for multifunctional wearable nanocomposite hydrogel sensors.

No abstract