SnSe Nanosheets: From Facile Synthesis to Applications in Broadband Photodetections

In recent years, using two-dimensional (2D) materials to realize broadband photodetection has become a promising area in optoelectronic devices. Here, we successfully synthesized SnSe nanosheets (NSs) by a facile tip ultra-sonication method in water-ethanol solvent which was eco-friendly. The carrier dynamics of SnSe NSs was systematically investigated via a femtosecond transient absorption spectroscopy in the visible wavelength regime and three decay components were clarified with delay time of tau(1) = 0.77 ps, tau(2) = 8.3 ps, and tau(3) = 316.5 ps, respectively, indicating their potential applications in ultrafast optics and optoelectronics. As a proof-of-concept, the photodetectors, which integrated SnSe NSs with monolayer graphene, show high photoresponsivities and excellent response speeds for different incident lasers. The maximum photo-responsivities for 405, 532, and 785 nm were 1.75 x 10(4) A/W, 4.63 x 10(3) A/W, and 1.52 x 10(3) A/W, respectively. The photoresponse times were similar to 22.6 ms, 11.6 ms, and 9.7 ms. This behavior was due to the broadband light response of SnSe NSs and fast transportation of photocarriers between the monolayer graphene and SnSe NSs.

Automated summary

In recent years, the use of two-dimensional materials for broadband photodetection has become a promising area in optoelectronic devices. Synthesized SnSe nanosheets integrated with monolayer graphene showed high photoresponsivities and excellent response speeds for different incident lasers, demonstrating their potential for advanced optoelectronic applications.