A self-powered flexible-vision electronic skin based on piezophototronic GaN nanowires for rapid image recognition

A self-powered flexible-vision electronic skin for rapid image recognition has been fabricated from piezophototronic GaN nanowires. The basic structure of each photodetecting pixel consists of horizontally-aligned GaN nanowires crossing a cross-finger electrode, and 6 x 6 photodetecting pixels that form a patterned sensing matrix. The working mechanism is based on the piezophototronic effect, and the device can harvest a tiny amount of mechanical energy and directly output photodetecting signals without any external electrical power. The output piezoelectric voltage is significantly dependent on UV illumination, and the response is up to similar to 76 for 80 mu W cm(-2) light. The response and recovery times are very short. A practical application of the device for rapid image recognition has been simply demonstrated, and this shows the potential for realizing an artificial intelligent retina. This work can promote the development of wearable flexible electronics and expand the scope of self-powered nanosystems.