Self-Powered Nano Pt/Amorphous Ga₂O₃/Crystalline CuCrO₂ Heterostructure Solar-Blind Photodetector With High Responsivity and Detectivity

We report for the first time self-powered solar-blind photodetectors (SBPDs) based on the nano Pt/amorphous Ga₂O₃/crystalline CuCrO₂ heterostructure. Our PDs exhibit a high photo-to-dark-current ratio of 3.91 × 10⁶, an impressive responsivity of 3.57 A/W, an ultrahigh detectivity of 2.56 × 10¹⁴ Jones, and a high external quantum efficiency of 1748.4 %, surpassing most reported self-powered Ga₂O₃-based heterostructure SBPDs. Such outstanding performances can be attributed to nano Pt, which produces the localized Schottky junction, localized electric field, and localized surface plasmon resonance effect. Moreover, type-II band alignment is identified at the amorphous Ga₂O₃/crystalline CuCrO₂ interface via X-ray photoelectron spectroscopy, which facilitates the separation of photogenerated carriers. This study provides a novel strategy for designing high-performance self-powered SBPDs.