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Monolayer black phosphorus by sequential wet-chemical surface oxidation.

ABSTRACT: We report a straightforward chemical methodology for controlling the thickness of black phosphorus flakes down to the monolayer limit by layer-by-layer oxidation and thinning, using water as solubilizing agent. Moreover, the oxidation process can be stopped at will by two different passivation procedures, namely the non-covalent functionalization with perylene diimide chromophores, which prevents the photooxidation, or by using a protective ionic liquid layer. The obtained flakes preserve their electronic properties as demonstrated by fabricating a BP field-effect transistor (FET). This work paves the way for the preparation of BP devices with controlled thickness.

SUBMITTER: Wild S

PROVIDER: S-EPMC6369675 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Monolayer black phosphorus by sequential wet-chemical surface oxidation.

Wild Stefan S Lloret Vicent V Vega-Mayoral Victor V Vella Daniele D Nuin Edurne E Siebert Martin M Koleśnik-Gray Maria M Löffler Mario M Mayrhofer Karl J J KJJ Gadermaier Christoph C Krstić Vojislav V Hauke Frank F Abellán Gonzalo G Hirsch Andreas A

RSC advances 20190125 7

We report a straightforward chemical methodology for controlling the thickness of black phosphorus flakes down to the monolayer limit by layer-by-layer oxidation and thinning, using water as solubilizing agent. Moreover, the oxidation process can be stopped at will by two different passivation procedures, namely the non-covalent functionalization with perylene diimide chromophores, which prevents the photooxidation, or by using a protective ionic liquid layer. The obtained flakes preserve their ...[more]

PMID: 30854196

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