Space-Confined Growth of 2D InI Showing High Sensitivity in Photodetection

Layered InI has a great potential in optoelectronic applications due to its direct wide tunable bandgap. However, there is no single report about its 2D synthesis. Here, the growth of high-quality and ultrathin InI flake (as thin as 8 nm) is reported via space-confined physical vapor deposition. Impressively, an InI flake-based photodetector exhibits an ultralow off-state current of approximate to 4.2 x 10(-12) A, high on/off photocurrent ratio of 10(4), excellent detectivity of 4.2 x 10(12) Jones, a high-speed response time of 10 ms, as well as excellent effective quantum efficiency of 1600%, suggesting its promising applications in optoelectronics.