Transparent, flexible MAPbI3 perovskite microwire array passivated with ultra-hydrophobic supramolecular assembly for stable and high-performance photodetectors
The emergence of organic-inorganic hybrid perovskites (OHPs) has revolutionised the potential performance of optoelectronic devices, most perovskites are opaque and hence incompatible with transparent optoelectronics, and sensitive to environmental degradation. Here, a single-step fabrication of ultra-long MAPbI3 perovskite microwire array over a large-area using stencil lithography based on a sequential vacuum sublimation. The environmental stability of MAPbI3 is empowered a newly designed and synthesized transparent supramolecular self-assembly, based on a mixture of two tripodal L-Phe-C11H23/C7F15 molecules, which showed a contact angle of 105 and served as ultra-hydrophobic passivation layer for more than 45 days in ambient atmosphere. The MAPbI3 microwire array passivated with supramolecular self-assembly demonstrate for the first time both excellent transparency of ~89% at 550 nm and remarkable photoresponse with photo-switching ratio of ~104, responsivity of 789 A/W, detectivity of 1014 Jones, linear dynamic range of ~ 122 dB, and rise time of 432 µs. Furthermore, the photodetector fabricated on flexible PET substrate demonstrated robust mechanical flexibility even beyond 1200 bending cycles. Therefore, the scalable stencil lithography and supramolecular passivation approaches have the potential to deliver next-generation transparent, flexible, and stable optoelectronics.