TY - JOUR
T1 - Selective Chemical Response of Transition Metal Dichalcogenides and Metal Dichalcogenides in Ambient Conditions
AU - Park, Jun Hong
AU - Vishwanath, Suresh
AU - Wolf, Steven
AU - Zhang, Kehao
AU - Kwak, Iljo
AU - Edmonds, Mary
AU - Breeden, Michael
AU - Liu, Xinyu
AU - Dobrowolska, Margaret
AU - Furdyna, Jacek
AU - Robinson, Joshua A.
AU - Xing, Huili Grace
AU - Kummel, Andrew C.
N1 - Funding Information:
This work was supported by NSF Grant DMR 1207213, NSF Grant ECCS 1433490, NSF Grant DMR14-00432, AFOSR, and LEAST-STARnet, a Semiconductor Research Corp. program, sponsored by MARCO and DARPA and by SRC NRI SWAN. Instrumental support from NSF NNCI award number is ECCS-1542148 is gratefully acknowledged.
PY - 2017/8/30
Y1 - 2017/8/30
N2 - To fabricate practical devices based on semiconducting two-dimensional (2D) materials, the source, channel, and drain materials are exposed to ambient air. However, the response of layered 2D materials to air has not been fully elucidated at the molecular level. In the present report, the effects of air exposure on transition metal dichalcogenides (TMD) and metal dichalcogenides (MD) are studied using ultrahigh-vacuum scanning tunneling microscopy (STM). The effects of a 1-day ambient air exposure on MBE-grown WSe2, chemical vapor deposition (CVD)-grown MoS2, and MBE SnSe2 are compared. Both MBE-grown WSe2 and CVD-grown MoS2 display a selective air exposure response at the step edges, consistent with oxidation on WSe2 and adsorption of hydrocarbon on MoS2, while the terraces and domain/grain boundaries of both TMDs are nearly inert to ambient air. Conversely, MBE-grown SnSe2, an MD, is not stable in ambient air. After exposure in ambient air for 1 day, the entire surface of SnSe2 is decomposed to SnOx and SeOx, as seen with X-ray photoelectron spectroscopy. Since the oxidation enthalpy of all three materials is similar, the data is consistent with greater oxidation of SnSe2 being driven by the weak bonding of SnSe2.
AB - To fabricate practical devices based on semiconducting two-dimensional (2D) materials, the source, channel, and drain materials are exposed to ambient air. However, the response of layered 2D materials to air has not been fully elucidated at the molecular level. In the present report, the effects of air exposure on transition metal dichalcogenides (TMD) and metal dichalcogenides (MD) are studied using ultrahigh-vacuum scanning tunneling microscopy (STM). The effects of a 1-day ambient air exposure on MBE-grown WSe2, chemical vapor deposition (CVD)-grown MoS2, and MBE SnSe2 are compared. Both MBE-grown WSe2 and CVD-grown MoS2 display a selective air exposure response at the step edges, consistent with oxidation on WSe2 and adsorption of hydrocarbon on MoS2, while the terraces and domain/grain boundaries of both TMDs are nearly inert to ambient air. Conversely, MBE-grown SnSe2, an MD, is not stable in ambient air. After exposure in ambient air for 1 day, the entire surface of SnSe2 is decomposed to SnOx and SeOx, as seen with X-ray photoelectron spectroscopy. Since the oxidation enthalpy of all three materials is similar, the data is consistent with greater oxidation of SnSe2 being driven by the weak bonding of SnSe2.
UR - http://www.scopus.com/inward/record.url?scp=85028713892&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85028713892&partnerID=8YFLogxK
U2 - 10.1021/acsami.7b08244
DO - 10.1021/acsami.7b08244
M3 - Article
C2 - 28805363
AN - SCOPUS:85028713892
VL - 9
SP - 29255
EP - 29264
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
SN - 1944-8244
IS - 34
ER -