Recently, a zipper two-dimensional (2D) material Bi 2 O 2 Se belonging to the layered bismuth oxychalcogenide (Bi 2 O 2 X: X = S, Se, Te) family, has emerged as an alternate candidate to van der Waals 2D materials for high-performance electronic and optoelectronic applications. This hints towards exploring the other members of the Bi 2 O 2 X family for their true potential and bismuth oxysulfide (Bi 2 O 2 S) could be the next member for such applications. Here, we demonstrate for the first time, the scalable room-temperature chemical synthesis and near-infrared (NIR) photodetection of ultrathin Bi 2 O 2 S nanosheets. The thickness of the freestanding nanosheets was around 2–3 nm with a lateral dimension of ∼80–100 nm. A solution-processed NIR photodetector was fabricated from ultrathin Bi 2 O 2 S nanosheets. The photodetector showed high performance, under 785 nm laser illumination, with a photoresponsivity of 4 A W −1 , an external quantum efficiency of 630%, and a normalized photocurrent-to-dark-current ratio of 1.3 × 10 10 per watt with a fast response time of 100 ms. Taken together, the findings suggest that Bi 2 O 2 S nanosheets could be a promising alternative 2D materialmore »
Chemically exfoliated nanosheets of β-Bi 2 O 3
Exploring two dimensional (2D) materials is important for further developing the field of quantum materials. However, progress in 2D material development is limited by difficulties with their production. Specifically, freestanding 2D materials with bulk non-layered structures remain particularly challenging to prepare. Traditionally, chemical or mechanical exfoliation is employed for obtaining freestanding 2D materials, but these methods typically require layered starting materials. Here we put forth a method for obtaining thin layers of
- Publication Date:
- NSF-PAR ID:
- 10372710
- Journal Name:
- Journal of Physics: Materials
- Volume:
- 5
- Issue:
- 4
- Page Range or eLocation-ID:
- Article No. 044004
- ISSN:
- 2515-7639
- Publisher:
- IOP Publishing
- Sponsoring Org:
- National Science Foundation
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