Group-10 transition metal dichalcogenides (TMDs) with distinct optical
and tunable electrical properties have exhibited great potential for various
optoelectronic applications. Herein, a self-powered photodetector is developed
with broadband response ranging from deep ultraviolet to near-infrared
by combining FA1−xCsxPbI3 perovskite with PdSe2 layer, a newly discovered
TMDs material. Optoelectronic characterization reveals that the as-assembled
PdSe2/perovskite Schottky junction is sensitive to light illumination
ranging from 200 to 1550 nm, with the highest sensitivity centered at
≈800 nm. The device also shows a large on/off ratio of ≈104, a high responsivity
(R) of 313 mA W−1, a decent specific detectivity (D*) of ≈1013 Jones,
and a rapid response speed of 3.5/4 μs. These figures of merit are comparable
with or much better than most of the previously reported perovskite
detectors. In addition, the PdSe2/perovskite device exhibits obvious sensitivity
to polarized light, with a polarization sensitivity of 6.04. Finally, the
PdSe2/perovskite detector can readily record five “P,” “O,” “L,” “Y,” and “U”
images sequentially produced by 808 nm. These results suggest that the
present PdSe2/perovskite Schottky junction photodetectors may be useful
for assembly of optoelectronic system applications in near future.