Ti₃C₂T_x MXene-RAN van der Waals Heterostructure-Based Flexible Transparent NIR Photodetector Array for 1024 Pixel Image Sensing Application

The enriched surface functional group such as -OH termination and unique 2D structure of Ti₃C₂T_x MXene provide the feasibility to form hydrogen bonds with organic photosensitive materials as van der Waals heterostructures, thus can realize the improved photoresponsivity of near infrared (NIR) photodetectors (PDs). In this work, an organic–inorganic van der Waals heterostructure-based NIR PD array is designed using Ti₃C₂T_x MXene as conductive electrodes and RAN film as active materials (Ti₃C₂T_x-RAN PDs). The on-off ratio of the fabricated devices shows 6.25 times higher than that of PDs using thermal evaporated Au electrode (Au-RAN PDs) under 1064 nm laser excitations. The fabricated Ti₃C₂T_x-RAN NIR PDs also possess outstanding mechanical stability with no obvious photoresponse degradation under different bending states and high transparency with a transmittance above 70% in the visible region. Owing to the high performance of the Ti₃C₂T_x-RAN PDs, a 1024-pixel (32 × 32) image sensor array is fabricated to achieve delicate, vivid, and higher resolution imaging of a “deer,” opening up a new avenue for the biomimetic vision and flexible wearable accurate image sensing.