SnSe2 Quantum Dots: Facile Fabrication and Application in Highly Responsive UV-Detectors

Abstract

Synthesizing quantum dots (QDs) using simple methods and utilizing them in optoelectronic devices are active areas of research. In this paper, we fabricated SnSe2 QDs via sonication and a laser ablation process. Deionized water was used as a solvent, and there were no organic chemicals introduced in the process. It was a facile and environmentally-friendly method. We demonstrated an ultraviolet (UV)-detector based on monolayer graphene and SnSe2 QDs. The photoresponsivity of the detector was up to 7.5 × 106 mAW−1, and the photoresponse time was ~0.31 s. The n–n heterostructures between monolayer graphene and SnSe2 QDs improved the light absorption and the transportation of photocarriers, which could greatly increase the photoresponsivity of the device.

SnSe Nanosheets: From Facile Synthesis to Applications in Broadband Photodetections

“…This may be due to the increase of the concentration of photoexcited carriers under higher incident power, which results in the carriers forming an electrical field and the formed electrical field is in reverse to the built-in field, thereby hindering the transport of photogenerated electron-hole pairs. The same change was reported in previous studies which constructed monolayer graphene photodetectors with a similar structure [ 5 , 6 , 7 , 8 , 9 , 10 , 41 , 42 ]. Furthermore, the responsivity reduced as the wavelength of light increases, which basically follows the absorption spectrum of the SnSe NSs ( Figure 2 d).…”

“…This can be attributed to the large and broad absorption of SnSe NSs and the charge transfer between SnSe NSs and graphene. However, the high responsivity is restricted to the bandgap absorption of SnSe NSs and this is a common characteristic for photodetectors having a similar structure, as reported in previous studies [ 7 , 8 , 9 , 10 , 41 , 42 ].…”

“…In addition, the photodetector still exhibited a clear channel photocurrent of ~8.0 μA at V DS = 0.05 V under 785 nm light ( Figure 7 e). The rise and fall times of 9.7 and 16.6 ms, respectively ( Figure 7 f), suggest a faster photoresponse time than previous photodetectors based on hybrid graphene [ 5 , 6 , 7 , 8 , 9 , 10 , 41 , 42 ]. It was clear that there were two processes in the channel current, which were the fast process and the slow process.…”

Functional Nanostructures for Sensors, Optoelectronic Devices, and Drug Delivery

“…The scope of the Special Issue “Functional Nanostructures for Sensors, Optoelectronic Devices, and Drug Delivery” was to provide an overview of the current research activities in the field of nanostructured materials, with a particular emphasis on their potential applications for sensors [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ], optoelectronic devices [ 10 , 11 , 12 , 13 , 14 , 15 ], and biomedical systems [ 16 , 17 , 18 ]. The Special Issue welcomed the submission of original research articles [ 1 , 2 , 3 , 4 , 5 , 6 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ] and comprehensive reviews that demonstrated or summarized significant advances in the above-mentioned research fields. Next, the Special Issue collected fifteen selected original research papers and three comprehensive reviews [ 7 , 8 , 18 ] on various topics of nanostructured materials and relative characterization spanning from fundamental research to technological applications.…”

“…n-n heterostructures based on graphene monolayer and SnSe 2 quantum dots (QDs) showing good performance in the light absorption and the transportation of photocarriers were reported by Li et al Uniformly distributed SnSe 2 quantum dots were synthesized at room temperature by a facile and environment-friendly methodology. The graphene monolayer and SnSe 2 quantum dots UV-detector showed fast photoresponse time of ~0.31 s, and its photoresponsivity was up to 7.5 × 10 6 mA W −1 , which are promising for optoelectronic applications [ 14 ].…”