TY  - JOUR
AU  - Mastria, Rosanna
AU  - Scarfiello, Riccardo
AU  - Altamura, Davide
AU  - Giannini, Cinzia
AU  - Liscio, Andrea
AU  - Kovtun, Alessandro
AU  - Bianco, Giuseppe Valerio
AU  - Bruno, Giovanni
AU  - Grillo, Vincenzo
AU  - Tavabi, Amir H.
AU  - Dunin-Borkowski, Rafal E.
AU  - Nobile, Concetta
AU  - Cola, Adriano
AU  - Cozzoli, P. Davide
AU  - Gambino, Salvatore
AU  - Rizzo, Aurora
TI  - In-plane Aligned Colloidal 2D WS2 Nanoflakes for Solution-Processable Thin Films with High Planar Conductivity
JO  - Scientific reports
VL  - 9
IS  - 1
SN  - 2045-2322
CY  - [London]
PB  - Macmillan Publishers Limited, part of Springer Nature
M1  - FZJ-2020-02665
SP  - 9002
PY  - 2019
AB  - Two-dimensional transition-metal dichalcolgenides (2D-TMDs) are among the most intriguing materials for next-generation electronic and optoelectronic devices. Albeit still at the embryonic stage, building thin films by manipulating and stacking preformed 2D nanosheets is now emerging as a practical and cost-effective bottom-up paradigm to obtain excellent electrical properties over large areas. Herein, we exploit the ultrathin morphology and outstanding solution stability of 2D WS2 colloidal nanocrystals to make thin films of TMDs assembled on a millimetre scale by a layer-by-layer deposition approach. We found that a room-temperature surface treatment with a superacid, performed with the precise scope of removing the native insulating surfactants, promotes in-plane assembly of the colloidal WS2 nanoflakes into stacks parallel to the substrate, along with healing of sulphur vacancies in the lattice that are detrimental to electrical conductivity. The as-obtained 2D WS2 thin films, characterized by a smooth and compact morphology, feature a high planar conductivity of up to 1 μS, comparable to the values reported for epitaxially grown WS2 monolayers, and enable photocurrent generation upon light irradiation over a wide range of visible to near-infrared frequencies.
LB  - PUB:(DE-HGF)16
C6  - pmid:31227748
UR  - <Go to ISI:>//WOS:000472477300001
DO  - DOI:10.1038/s41598-019-45192-1
UR  - https://juser.fz-juelich.de/record/878152
ER  -