An ultra-low dark current, high-performance photodetector based on CVD-grown Bi2TeO5

Abstract

Low-dimensional materials, particularly quasi-2D semiconductors like bismuth oxychalcogenides (BiOX), offer unique advantages for advanced photodetection due to van der Waals integration and quantum-confined properties. In this research, Bi₂TeO₅ nanosheets were successfully grown using a chemical vapor deposition method. The resulting Bi₂TeO₅ photodetector exhibited remarkable performance characteristics. Specifically, it demonstrated an open circuit voltage of −1.14 V, a depolarization field of 5.7 × 10⁷ V m⁻¹, a remarkably low dark current of 10⁻¹⁵ A, an impressive on/off ratio of 10³, a responsivity of 466.80 mA W⁻¹, a detectivity of 4.23 × 10¹² Jones, and an EQE of 218.44% at 8 V bias. The work highlights the significant potential of Bi₂TeO₅ and provides new design strategies for developing next-generation 2D photodetectors.