High-performance self-powered color filter-free blue photodetector based on wide-bandgap halide perovskites

Blue photodetectors (PDs) are attracting great attention for various applications. Commercial blue PDs based on inorganic GaP or InGaN absorbers are limited by their expensive, complex, and high-temperature fabrication techniques. Organic absorber-based blue PDs still have much lower photodetecting properties than inorganic blue PDs. In this study, a high-performance self-powered blue PD is developed using methylammonium lead halide (MAPbX₃; X = I, Br, and Cl) perovskites based on the economic and facile solution process at low temperatures. Optimal composition is obtained through halide-composition engineering. Our best-performing device exhibits an average external quantum efficiency and an average detectivity of 42.7% and 8.65 × 10¹¹ Jones, respectively, within the blue region. The peak responsivity of the proposed PD is 0.174 A W⁻¹ at 455 nm, which is comparable to that of commercial gallium phosphide blue PD (0.180 A W⁻¹ at 470 nm). Moreover, the proposed device exhibits excellent environmental stability under ambient air conditions. These findings will act as a basis for next-generation image sensor technologies, such as vertically stacked red/green/blue PDs.