mechanical energy exists extensively in our daily life, such as vibration, wind, and waves. [3] However, most of this energy is wasted and long-neglected. For one thing, environmental mechanical energy is random in amplitude, low in frequently, widely distributed, unstable, and random. Therefore, the design of effective and environmental-friendly energy harvesters still has lots of technical and economic challenges. [4] Besides, IoT has made a great progress with the development of sensor, wireless communication, and micro/nanotechnology. [5] IoT enables collecting and processing data among the whole network, which consists of huge numbers of widely distributed sensors or smart devices. But how to supply adaptive and sustainable energy for nodes of IoT is a big task even though each node only needs a tiny power. According to the characteristic of wide distribution, harvesting environmental mechanical energy is an attractive approach to powering the nodes of IoT. [6]

Triboelectric nanogenerators (TENGs) can be applied for the next generation of artificial intelligent products, where skin-like tactile sensing advances the ability of robotics to feel and interpret environment. In this paper, a flexible and thin tactile sensor was developed on the basis of dual-mode TENGs. The effective transduction of touch and pressure stimulus into independent and interpretable electrical signals permits the instantaneous sensing of location and pressure with a plane resolution of 2 mm, a high-pressure-sensing sensitivity up to 28 mV·N, and a linear pressure detection ranging from 40 to 140 N. Interestingly, this self-powered dual-mode sensor can even interpret contact and hardness of objects by analyzing the shape of the current peak, which makes this low-cost TENG-based sensor promising for applications in touch screens, electronic skins, healthcare, and environmental survey.