Here
we report on a novel, noninvasive route for operando tailoring
of the charge transport properties of metal/WS2 contacts
without the negative impacts to two-dimensional materials arising
from conventional doping methods. The doping level of thin WS2 flakes supported on insulating mica is susceptible to local
charge variations induced by the presence of a hydration layer between
mica and WS2. We demonstrate, via the use of several complementary
scanning probe techniques, that the direct control of the state and
thickness of this intercalated water film controls the charge injection
properties of Pt/WS2 nanocontacts. A switch from unipolar
to ambipolar transport was achieved by environmentally controlling
the thickness of the intercalated water. We show that the effect persists
even for multilayer flakes and that it is completely reversible, opening
a new route toward the realization of novel electronics with environmentally
controllable functionalities.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.