A Neuron‐Readable Artificial Photoreceptor Composed of Photodeformable Liquid Crystal Polymers and Piezoelectric Materials

• Published in: Advanced functional materials Vol. 33; no. 23
• Main Authors: Peng, Bo, Chen, Xueli, Yu, Guodong, Xu, Fan, Yang, Ruyi, Yu, Zhenghang, Wei, Jia, Zhu, Guodong, Qin, Lang, Zhang, Jiayi, Shen, Qundong, Yu, Yanlei
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.06.2023
• Subjects: artificial photoreceptors; Circuits; Electric potential; Electronic implants; Eye diseases; Liquid crystal polymers; Liquid crystals; Materials science; neuron‐readable devices; photodeformations; Photoreceptors; piezoelectric materials; Piezoelectricity; Polyvinylidene fluorides; Signal transduction; Voltage
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202214172

Artificial photoreceptors are extensively developed to help the patients with serious eye diseases by converting light into electric signals. However, the existing systems still suffer from poor output signals, restricting signal transduction to cells. Here, a neuron‐readable artificial photoreceptor with significant voltage output is constructed by using photodeformable liquid crystal polymers (LCPs) and polyvinylidene fluoride trifluoroethylene (P(VDF‐TrFE)). The significant voltage output originates from light‐stress‐electricity conversion, where the photo‐induced stress is attributed to the free volume expansion of the photodeformable LCPs and subsequently converts them into strong electric signals by the P(VDF‐TrFE) layer. The photo‐induced open‐circuit voltage reaches up to 0.79 ± 0.02 V, which is, to the knowledge, 19 times higher than the maximum voltage (0.04 V) that has been reported to date. Hence, such artificial photoreceptor successfully transduces photo‐induced electric signals to cells and tissues, communicates with the neurons, and triggers spiking activities in blind retinas. Besides, visual image recognition is demonstrated in a pixelated matrix by analyzing electric signals of each unit. This artificial photoreceptor opens new opportunities for the combination of the photodeformability and piezoelectricity, providing an avenue to develop neuron‐readable artificial retinas and implantable sensors. The artificial photoreceptor consisting of photodeformable liquid crystal polymers and piezoelectric materials is fabricated to output photoelectric signals by conversion of light‐stress‐electric signals, whose voltage (0.79 V) is 19 times higher compared with reported work. More importantly, the artificial photoreceptor transduced photo‐induced electric signals to cells and triggered spiking activities, which indicated the direct communication with neurons in blind retinas.