TaS₂ Nanosheets Decorated with SnS₂ Nanosheet/Reduced Graphene Oxide Composites for Broadband Photodetectors

The demand for inexpensive, efficient photoelectrosensitive materials for photosensing applications still exists to replace the expensive and highly intricate systems. Herein, we have designed an SnS 2 -/rGO-decorated 2D-TaS 2 heterostructure for broadband photodetector applications and also studied its photoelectrochemical properties. According to the photoelectrochemical measurements, the 2D-TaS 2 /SnS 2 –rGO heterostructure shows 10 times enhancement in the photocurrent density, i.e., 2.23 mA/cm 2 at −0.98 V under light illumination, than that of the bare 2D-TaS 2 which shows 0.25 mA/cm 2 at −0.98 V. The electrochemical impedance spectroscopy analysis depicts a low charge transfer resistance ( R ct ) value, indicating that charge carrier migration is more preferred in the heterostructure, thus confirming higher activity toward photoelectrochemical applications. The applied bias to photon-to-current efficiency, ABPE % for heterostructure 2D-TaS 2 /SnS 2 –rGO, is nearly 33 times higher than that of 2D-TaS 2 . Furthermore, we have designed an efficient photodetector based on the 2D-TaS 2 /SnS 2 –rGO heterostructure, showing photoresponse over a wide range (200–1550 nm). The fabricated heterostructure exhibits nearly 10 times higher photoelectrocatalytic performance than that of the 2D-TaS 2 in the ultraviolet (UV)–near IR regime and shows a responsivity of 1.79 mA W –1 in the UV regime. The transient photoresponse measurements confirm the stability of the photocatalyst with a rise and fall time of ∼3 s. These results establish the feasibility of fabricating the 2D-TaS 2 /SnS 2 –rGO heterostructure at room temperature for broadband photodetection.