In recent years, the development of electronic skin and smart wearable body sensors has put forward high requirements for flexible pressure sensors with high sensitivity and large linear measuring range. However, it turns out to be difficult to increase both of them simultaneously. In this paper, a flexible capacitive pressure sensor based on a porous carbon conductive pastepolydimethylsiloxane composite is reported, the sensitivity and the linear measuring range of which were developed using multiple methods including adjusting the stiffness of the dielectric layer material, fabricating a microstructure and increasing the dielectric permittivity of the dielectric layer. The capacitive pressure sensor reported here has a relatively high sensitivity of 1.1 kPa −1 and a large linear measuring range of 10 kPa, making the product of the sensitivity and linear measuring range 11, which is higher than that of the most reported capacitive pressure sensors to our best knowledge. The sensor has a detection of limit of 4 Pa, response time of 60 ms and great stability. Some potential applications of the sensor were demonstrated, such as arterial pulse wave measuring and breath measuring, which shows it as a promising candidate for wearable biomedical devices. In addition, a pressure sensor array based on the material was also fabricated and it could identify objects in the shape of different letters clearly, which shows promising application in future electronic skins.

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Electronic skin (e‐skin) integrating pressure sensors and strain sensors has shown great potential applications in smart robotics and healthcare monitoring for their flexibility and wearability. However, making the sensor low cost and highly durable for industrialization and commercialization is still a problem to be addressed. An embedded 3D printing technology is developed based on novel thermosetting printing ink which is prepared using the Ecoflex and carbon nanoparticles. The properties of the printing ink including printability and electrical conductivity are first studied and then optimized. By using this technology, a glove‐shaped e‐skin integrating both strain sensors and pressure sensors is fabricated, and the properties of the sensors are studied. Both types of sensors have excellent stability and reliability which are verified by multiple long‐term measurements (10 000 testing cycles). Specifically, the sensors possess a great shock resistance and high durability which are significant for application in real life. Furthermore, some applications for human activity monitoring and personal healthcare are demonstrated, including complex gesture recognition using 15 strain sensors, hardness sensing using pressure sensors coupled with strain sensors, and arterial pulse measurement using pressure sensors, which are promising for smart robotic sensing and wearable biomedical devices.

Organic–inorganic two-dimensional (2D) perovskite is an optoelectronic material, with quantum-well structure and improved moisture stabilities, which has been widely used in various optoelectronic devices recently. In this review, the structure and properties of organic–inorganic 2D perovskite materials are first briefly introduced. After that, according to the different photoelectron coupling mechanisms, the recent progress of typical 2D perovskite-based optoelectronic devices is described in detail: including photodetectors, light-emitting diodes, solar cells, and lasers, as well as some optoelectronic devices (e.g., optical memory and optical synapses). We analyzed the influence of structure, manufacturing process, and material selection on device performance and showed promising progress in different applications. Subsequently, we proposed the possible breakthrough development direction of 2D perovskite-based optoelectronic devices in the coming years. This work points out the way for future progress of 2D perovskite-based optoelectronic devices, which is conducive to further improving device performance and inspiring designs of high-performance organic–inorganic 2D perovskite-based optoelectronic devices.