Ultra-High Detectivity MBene/Si vdW Schottky Photodiode for Color Single-Pixel Imaging

The color single-pixel imaging (SPI) has received significant attention due to its ability to provide more comprehensive real-world information compared to grayscale imaging. The performance of single-pixel photodetector is the primary determinant for the quality of color SPI. Silicon-based Schottky photodiodes provide desirable qualities for the essential requirements of high detectivity in high resolution color SPI. Herein, a novel Mo4/3B2-XTZ/Si hexagonal micro-hole array (SiHMA) van der Waals (vdW) Schottky photodiode is first constructed for application in color SPI. The resultant Schottky junction possesses a Schottky barrier height up to 1.18 eV, thus leading to a dark current density of 1.47 x 10-13 A cm-2 and an ultra-high detectivity of 4.4 x 1014 Jones at zero bias voltage, which are superior to most of Si-based Schottky photodiodes reported and even some commercial Si photodiodes thus far. Importantly, the high detectivity and low dark current density of the photodiode allow for the use as a photodetector in high resolution Hadamard SPI. Notably, a high-quality 256 x 256-pixel color image can be successfully achieved under even 25% sampling rate without an additional filter circuit. This work opens an avenue toward the fabrication of high detectivity Schottky photodiode for high quality color SPI. An ultra-high detectivity MBene/Si van der Waals (vdW) Schottky photodiode is first constructed for color single-pixel imaging. The device exhibits excellent performance in terms of a dark current density of 1.47 x 10-13 Acm-2 and andetectivity of 4.4 x 1014 Jones. A high-quality 256 x 256-pixel color image can be successfully achieved without an additional filter circuit.image