Highly-flexible and -stable deep-ultraviolet photodiodes made of graphene quantum dots sandwiched between graphene layers. (April 2019)

• Record Type: Journal Article
• Authors: Jang, Chan Wook; Shin, Dong Hee; Choi, Suk-Ho
• Is Part Of: Dyes and pigments. Volume 163(2019)
• Page Start: 238
• Page End: 242
• Publication Date: 2019-04
• Subjects: Graphene quantum dot -- Graphene -- Photodiode -- Flexible -- Deep-ultraviolet; Dyes and dyeing -- Periodicals; Pigments -- Periodicals; 667.2
• DOI: 10.1016/j.dyepig.2018.12.005
• Languages: English
• ISSNs: 0143-7208

Abstract

Abstract: We first report highly-flexible and -stable deep-ultraviolet (DUV) photodiodes (PDs) by employing graphene (GR) quantum dots (GQDs) sandwiched between top/bottom GR layers on polyethylene terephthalates (PETs). Here, 3-aminopropyl triethoxysilane is inserted between the bottom GR and the PET substrate to enhance the bending stabilities without degradation or delamination by the chemical bonding. GQDs of ∼5 nm diameter are proved to be well formed on the bottom GR by various structural and optical analysis tools including high-resolution transmission electron microscopy, Raman scattering, and photoluminescence. The DUV PDs exhibit 10 photo-/dark-current ratio, 0.1 AW -1 responsivity (R), and 1.1 × 10 13 cm Hz 1/2 /W detectivity at a wavelength of 254 nm. In addition, the R is reduced by only 13% even after 1000-times repeated bending tests at a bending curvature of 4 mm, and is almost consistent during the operations for 1000 h under ambient conditions. Highlights: First report of flexible deep UV photodiodes by employing graphene quantum dots. 0.1 AW -1 responsivity and 1.1 × 10 13 cm Hz 1/2 /W detectivity is achieved. Stability maintaining ∼87% of initial responsivity after 1000 bending cycles.