Circularly Polarized Photodetectors Based on Chiral Moiré Stacking Films of Electrospun ZnO Nanowires

Chiral semiconductors, with their distinct photoelectric responses to left- and right-handed circularly polarized light (CPL), are emerging as promising candidates for chiroptical sensing applications. This trend underscores the need to develop chiroptical photoelectric films with tunable handedness. In this study, we report the preparation of parallel-aligned ZnO nanowires (NWs) through oriented electrospinning and subsequent pyrolysis of precursor NWs. Chiral Moiré stacking films were created by stacking ZnO NWs with a controlled left-/right-handed rotation angle between successive layers. The film structural parameters and circular dichroism (CD) spectra were optimized. CPL photodetectors were developed using these chiroptical ZnO NW films and their hybridization with CsPbBr3 perovskite. The photodetector performance was investigated with a focus on responsivity (R), photodetectivity (D*), and the photocurrent asymmetry factor (gIph). Furthermore, discussion on the chiroptical and optoelectronic mechanisms intrinsic to these devices was conducted, shedding light on their potential for advanced CPL photodetection applications.