Nanorod-like nanocrystalline CsSnI3 and CNT composite thin film–based hybrid photodetector

Abstract

An experimental detail on the morphology engineering and characterizations of the all-inorganic Sn-based perovskite (here CsSnI3) thin films and their application in photodetectors are presented. In particular, we demonstrated that the chlorobenzene anti-solvent treatment during thin-film spin coating could effectively optimize the morphology properties of the obtained CsSnI3 thin film. SEM and AFM measurements showed the uniform thin film with nanorod-like nanocrystalline morphology. In addition, EDS and XPS measurements confirmed the low level of oxidation of the thin film, indicating good ambient stability. A planar photodetector was also made with the prepared thin film, and electrical characteristics were taken. The dark current and photocurrent were found in the range of 10−9 A and 10−7 A, respectively, with an on/off ratio of 102. The photoresponsivity was 10−5 AW−1. A further experiment was conducted to make composite thin films between CsSnI3 and CNTs for additional morphological engineering. The SEM measurement and Raman mapping manifested the nanonet-like morphology of the composite thin film. The quenching of the photoluminescence curve indicated the efficient photo-generated carrier extraction from the CsSnI3 matrix to CNTs. The absorption spectra also showed enhanced absorption ability of the prepared composite thin film. A hybrid photodetector made from the composite thin film showed dark current and photocurrent in the range of 10−6 A and 10−4 A, respectively, with an on/off ratio of 102. The photoresponsivity was 10−2 AW−1. Due to the combination of the CNTs with CsSnI3, the photoresponsivity increased 1000 times. At the same time, the hysteresis of the hybrid photodetector also reduced significantly compared to the pristine CsSnI3-based photodetector.

Space-Confined Chemical Vapor Deposition Synthesis of All-Inorganic CsSnI3 Perovskite Nanosheets

“…The dual peaks at 739.94 and 726.03 eV are from Cs 3d 5/2 and Cs 3d 3/2 , respectively, while the strong peaks at 495.6 and 486.6 eV are attributed to Sn 3d 5/2 and Sn 3d 5/2 , respectively. 22 The prominent peaks of I 3d 5/2 and I 3d 3/2 of I 3d are located at about 619.22 and 630.81 eV, respectively. The peak positions of Cs 3d, Sn 3d, and I 3d are in good agreement with the reported values for CsSnI 3 .…”

Lead‐Free Halide Perovskite Materials and Optoelectronic Devices: Progress and Prospective

“…The resulting device exhibited an R of 10 −2 A W −1 . [357] It must be noted that by slightly modifying the ASnX 3 unit formula toward lowerdimensional perovskites, the THPs stability can be further enhanced, while still maintaining a good photoresponse. [358][359][360] Considering THPs, it is interesting to observe that the performances offered by these materials closely approach, and sometimes surpass, the ones of commercially available Si-PDs characterized by an R(𝜆) ≈ 0.5 A W −1 and D ≈ 3 × 10 12 Jones.…”

“…Copyright 2020, American Chemical Society. f) Reproduced with permission [357]. Copyright 2022, Springer Nature.…”

Emerging Opportunities in Lead-Free and Lead–Tin Perovskites for Environmentally Viable Photodetector Applications

“…The deposition of the 3D Sn perovskite was implemented through CVD or solution-based approaches (Figure ). 3D perovskites with three different compositions, namely, CsSnI 3 , MASnI 3 , and FASnI 3 , have been employed in the fabrication of Sn perovskite photodetectors. ,,, Because of the low Sn vacancy formation energy and fast crystal growth of 3D perovskites, considerable effort has been expended on growing high-quality Sn perovskites. − …”

“…3D perovskites with three different compositions, namely, CsSnI 3 , MASnI 3 , and FASnI 3 , have been employed in the fabrication of Sn perovskite photodetectors. 95,113,120,126 Because of the low Sn vacancy formation energy and fast crystal growth of 3D perovskites, considerable effort has been expended on growing high-quality Sn perovskites. 130−133 Combining the CVD method and growth inside the alumina template was proposed as an exciting idea that would enable the development of vertically aligned Sn perovskite nanowires (NWs) (Figure 5a).…”