Poly(4-styrenesulfonate)-induced sulfur vacancy self-healing strategy for monolayer MoS<sub>2</sub> homojunction photodiode.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 28639620.
- Also identified by DOI 10.1038/ncomms15881 and PMC identifier 5489680.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
We establish a powerful poly(4-styrenesulfonate) (PSS)-treated strategy for sulfur vacancy healing in monolayer MoS<sub>2</sub> to precisely and steadily tune its electronic state. The self-healing mechanism, in which the sulfur vacancies are healed spontaneously by the sulfur adatom clusters on the MoS<sub>2</sub> surface through a PSS-induced hydrogenation process, is proposed and demonstrated systematically. The electron concentration of the self-healed MoS<sub>2</sub> dramatically decreased by 643 times, leading to a work function enhancement of ∼150 meV. This strategy is employed to fabricate a high performance lateral monolayer MoS<sub>2</sub> homojunction which presents a perfect rectifying behaviour, excellent photoresponsivity of ∼308 mA W<sup>-1</sup> and outstanding air-stability after two months. Unlike previous chemical doping, the lattice defect-induced local fields are eliminated during the process of the sulfur vacancy self-healing to largely improve the homojunction performance. Our findings demonstrate a promising and facile strategy in 2D material electronic state modulation for the development of next-generation electronics and optoelectronics.