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Ionic electrochemical actuators, which convert electrical energy into mechanical energy through electrochemical‐induced ion migration, show great potential in biomimetic soft robots. However, their applications are still limited due to the influence of the electrode materials and actuator performance. Here, an MXene/carbon nanotube (CNT) heterostructural electrode‐based ionic actuator is developed and realizes dexterous touch manipulation mimicking humans. In this MXene/CNT heterostructure, one‐dimensional CNTs are chemically interconnected into layered two‐dimensional MXene nanosheets, increasing their interlayer spacing, promoting mechanical stability, and enhancing specific surface area, which facilitates the ion migration and storage as well as electrochemical actuation. Accordingly, the MXene/CNT actuator can output excellent mechanical deformation under 2.5 V voltage, including large peak‐to‐peak deformation (displacement 24 mm, strain 1.54%), wide frequency response (0.1–15 Hz), large force (5 mN) and good cycling stability. The actuators can be used to construct artificial fingers to achieve gentle, multi‐point, variable frequency, and synergistic touching on fragile smartphone screens, including pressing a phone number to make a call and tapping an electronic drum. Especially, this finger can tap the drum at a high frequency (13 Hz), exceeding the tapping frequency that real human fingers can reach, which demonstrates its prospect in human‐computer interaction. [ABSTRACT FROM AUTHOR]

Electronic skins (E‐skins) capable of biomechanical/bioelectrical signal acquisition are intensively pursued for human‐centered healthcare of daily life. For practical use, it is highly desired, yet challenging, to mass‐produce E‐skins that are soft and breathable for wearing comfort, skin‐adhesive for robust signal acquisition, multi‐signal sensing for enhanced healthcare data. Herein, a scalable fabrication strategy for a bioinspired E‐skin (SPRABE‐skin) with a multi‐layered architecture is reported that integrates skin‐like softness, self‐protection, self‐adhesion, breathability, and bimodal sensing in a single patch. The fibrous thermoplastic polyurethane (TPU) scaffold endows the SPRABE‐skin with tissue‐like softness (Young's modulus of 3.36 MPa) and stretchability, good permeability to water vapor, and self‐protection against adverse loading events. A strain sensing layer composed of MXene‐carbon nanotubes@TPU (MXene‐CNT@TPU) composition exhibits ultra‐high sensitivity in a wide sensing range (gauge factor at strain of 485% reaches 63 494). An electrode layer made of MXene‐waterborne polyurethane (MXene‐WPU) provides a highly adhesive electrode‐skin interface, which enables the acquisition of biopotentials, such as electrocardiograph (ECG), electromyograph (EMG), electroencephalo‐graph (EEG), with improved fidelity even under various dynamic interferences. Finally, a SPRABE‐skin based human‐centered healthcare system is demonstrated that realizes the wireless, long‐duration, and dynamic monitoring of ECG and running activities. [ABSTRACT FROM AUTHOR]

A high sensitivity and large stretchability are desirable for strain sensors in wearable applications. However, these two performance indicators are contradictory, since the former requires a conspicuous structural change under a tiny strain, whereas the latter demands morphological integrity upon a large deformation. Developing strain sensors with both a high sensitivity (gauge factor (GF) > 100) and a broad strain range (>50%) is a considerable challenge. Herein, a unique Ti3C2Tx MXene nanoparticle–nanosheet hybrid network is constructed. The migration of nanoparticles leads to a large resistance variation while the wrapping of nanosheet bridges the detached nanoparticles to maintain the connectivity of the conductive pathways in a large strain region. The synergetic motion of nanoparticles and nanosheets endows the hybrid network with splendid electrical–mechanical performance, which is reflected in its high sensitivity (GF > 178.4) over the entire broad range (53%), the super low detection limit (0.025%), and a good cycling durability (over 5000 cycles). Such high performance endows the strain sensor with the capability for full‐range human motion detection. A strain sensor based on a Ti3C2Tx nanoparticle‐nanosheet hybrid network exhibits high sensitivity over the entire broad range due to the synergetic motion of nanoparticles and nanosheets and a constrained microcrack propagation mechanism. The migration of nanoparticles leads to a large resistance variation while the wrapping of the nanosheets bridges the nanoparticles and maintains the connectivity of the conductive pathways. [ABSTRACT FROM AUTHOR]