Helical Nanofiber Photoelectric Synaptic Devices for an Artificial Vision Nervous System.

Abstract

Inspired by the helical structure and the resultant exquisite functions of biomolecules, helical polymers have received increasing attention. Here, a series of poly(3-hexylthiophene)-<i>block</i>-poly(phenyl isocyanide) (P3HT-<i>b</i>-PPI) copolymers were prepared using a simple one-pot living polymerization method. Interestingly, the P3HT₈₀-<i>b</i>-PPI₃₀ films were found to have a helical nanofiber structure. The corresponding device has superior optoelectronic properties, such as a broadened spectral response range from the visible band to the deep ultraviolet (DUV) and an approximately 5-fold longer carrier decay time after DUV light stimulation. An energy consumption of 1.44 fJ per synaptic event was obtained, which is the lowest energy consumption achieved so far with DUV light stimulation. The encryption and decryption of images are implemented using an array of devices. Finally, a photoreceptor neural pathway was constructed to achieve early warning for the recognition of the display of harmful light. This research provides an effective strategy for the development of a novel optoelectronic synaptic device.