Piezo/Tribotronics Toward Smart Flexible Sensors

Smart, flexible, and self-powered sensory systems represent the developmental trend of information technology beyond Moore's law with versatility and diversity toward artificial intelligence. Piezo/tribotronics offer a direct linkage/triggering of the electrical output sensing signals with external mechanical actions in an active way, which is highly promising in smart and flexible sensors, intelligent human-machine interaction, and self-powered systems. Starting with the origin of piezo/triboelectric nanogenerators (PENGs/TENGs), herein, a review on the piezotronic devices based on 1D nanowires, 2D materials, 1D/2D mixed dimensional structures, PENG/TENG-gated three-terminal devices, and their applications in various multifunctional sensors is covered. In addition, a discussion is provided around how to improve the effectiveness in utilizing the piezo/triboelectric potential and fabricate smarter and more sophisticated electronic devices. Finally, future research concerns on piezo/triboelectric potential applications are summarized. There remains a massive space for the further development of piezotronics/tribotronics, which will be a multidisciplinary subject closely associated with soft electronics, neuromorphic devices, artificial intelligence, self-powered systems, and even ocean/space technologies.