Breaking the Trade‐off Between Responsivity and Response Time for Ga 2 O 3 Solar‐Blind Ultraviolet Photodetectors via Conductive‐Bridge Engineering for High‐Resolution Dynamic Imaging

ABSTRACT The inherent trade‐off between responsivity and response speed fundamentally limits the performance of solar‐blind ultraviolet photodetectors (SBUVPDs). Herein, an interfacial conductive‐bridge‐enhanced charge transport effect is proposed to overcome this limitation. Specifically, the 2D Nb 2 CT X MXene is introduced to form a charge transport channel at the surface of beta‐phase gallium oxide (β‐Ga 2 O 3 ). Aluminum (Al) nanoparticles (NPs) are incorporated as an efficient “carrier bridge” at the β‐Ga 2 O 3 /Nb 2 CT X MXene interface, effectively suppressing carrier accumulation and enhancing charge extraction. Meanwhile, decorating β‐Ga 2 O 3 with Al NPs enables a synergistic integration of plasmon‐enhanced light absorption and improved carrier dynamics via Schottky junction formation. Consequently, the β‐Ga 2 O 3 /Al NPs/Nb 2 CT X MXene SBUVPDs achieve remarkable performance, featuring a responsivity of 0.64 A/W, a detectivity of 1.01 × 10 13 Jones, a low dark current (8.94 × 10 −13 A), and a fast response time of 19.1 µs under 250 nm illumination. In addition, the responsivity of the SBUVPDs shows almost no degradation after 10 4 ON/OFF cycles. Finally, the device demonstrates excellent solar‐blind imaging capability for both static letters and real‐time moving objects. This work provides a novel and effective design strategy for next‐generation high‐performance SBUVPDs in imaging and sensing applications.