Wavelength-selective and stretchable infrared and visible photodetectors with coupled quantum dots/nanowires

Abstract

Bio inspired electronics such as eye-mimicking sensors are gaining huge attention due to their exceptional capabilities and perception abilities. For the future application of artificial intelligence in robotics and medical fields, however, it is necessary to incorporate functionalities of self-perception, IR detection, and stretchability/flexibility. Currently, these technologies rely on assistive components such as color filters and additional logic circuits. In this study, we introduce a wavelength-self-selective and stretchable photodetector (PD) based on CdSe nanowires (NWs) and PbS quantum dots (QDs). This hybrid PD is treated by simultaneous ligand exchange with NH4SCN to enhance the coupling between the NWs and the QDs, and to improve adhesion with the polymeric substrate. A heterojunction is designed to transfer electrons from the PbS QDs to the CdSe NWs upon the application of strain. Due to the stretchability of the net-structured CdSe NWs, the stretchable PD successfully detects visible and IR light under 50 % strain. Subsequently, we fabricate a vertically stacked two-channel hybrid PD system, which can successfully self-perceive the wavelength of visible and IR light. This development represents a significant step towards the realization of self-perceiving and stretchable sensor platform capable of detecting various wavelength.