High-Performance\nUltra-Broadband Photodetector Based\non Fe<sub>3</sub>O<sub>4</sub>/CrSiTe<sub>3</sub> Heterostructures

Photodetectors\nbased on advanced materials with a broad spectral\nphotoresponse, high sensitivity, huge integration ability, room-temperature\noperation, and stable environmental stability are highly desired for\ndiversified applications of imaging, sensing, and communication. Herein,\na high-performance ultra-broadband photodetector based on an ultrathin\ntwo-dimensional (2D) Fe<sub>3</sub>O<sub>4</sub> nanoflake heterostructure\nwith high sensitivity was designed. The photodetector response light\nwas from visible 405 nm to long-wave infrared (LWIR) 10.6 μm\nin ambient air. The competitive performances, including a high photoresponsivity\n(<i>R</i>) of 182.8 A W<sup>–1</sup>, fast speed\nwith the rise time τ<sub>r</sub> = 8.8 μs, and decay time\nτ<sub>d</sub> = 4.1 μs, were demonstrated in the visible\nrange. Notably, the device exhibits an excellent uncooled LWIR detection\nability, with a high <i>R</i> of 1.4 A W<sup>–1</sup> realized at a 1.5 V bias. In the full spectral range, the noise\nequivalent power is lower than 0.79 pW Hz<sup>–1/2</sup>, and\nspecific detectivity (<i>D</i>*) is higher than 4.9 ×\n10<sup>8</sup> cm Hz<sup>1/2</sup> W<sup>–1</sup> in ambient\nair. This work provides alternative ultrathin 2D materials for future\ninfrared optoelectronic devices.