Controllable low-temperature growth and enhanced photoelectrochemical water splitting of vertical SnS2 nanosheets on graphene. (20th December 2020)

• Record Type: Journal Article
• Authors: Seo, Dong-Bum; Kim, Min-Song; Trung, Tran Nam; Kim, Eui-Tae
• Is Part Of: Electrochimica acta. Volume 364(2020)
• Publication Date: 2020-12-20
• Subjects: Photoelectrochemistry -- SnS2 -- Graphene -- Nanosheets -- Chemical vapor deposition; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2020.137164
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: First demonstration of SnS2 nanosheets vertically aligned on graphene substrates. Controllable low-temperature growth of SnS2 nanosheets using chemical vapor deposition. Enhanced PEC activity through optimizing the microscopic structure of SnS2 nanosheets. Significantly increased photoconversion efficiency of vertical SnS2 nanosheets on graphene. Graphical abstract: Abstract: Two-dimensional (2D) SnS2 nanosheets vertically grown on graphene electrodes have still not been demonstrated despite their considerable research interest and potential for photoelectrochemical (PEC) applications. Herein, the controllable growth and enhanced PEC water-splitting performance of vertically aligned 2D SnS2 nanosheets on graphene are reported. The heterojunction quality of the graphene/2D SnS2 nanosheets was ensured by low-temperature growth at 230 °C using metalorganic chemical vapor deposition, resulting in significantly improved charge transfer properties. The PEC photocurrent density and photoconversion efficiency significantly increased upon insertion of a graphene layer. In addition, the 2D SnS2 nanosheet microscopic structure dependency of the PEC performance was systematically studied. The best PEC reactivity of the 2D SnS2 nanosheets was achieved at a height of ∼0.85 µm, corresponding to nearly the limit of the carrier diffusion length, and a thickness of ∼70 nm to balance the low interfacial contact resistance with an effective photogenerated carrier dynamics. These results, including the low-temperature vertical growth of 2D SnS2 on graphene, can effectively be utilized to exploit the full potential of 2D SnS2 for various PEC applications.