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Title: Sc 3 N@C 80 and La@C 82 doped graphene for a new class of optoelectronic devices
High-performance hybrid graphene photodetectors were prepared with endohedral fullerenes deposited on graphene using electrophoretic methods for the first time. Endohedral Sc 3 N@C 80 , which acts as an electron acceptor, was used and the ensuing electronic and optoelectronic properties were measured. Another endohedral fullerene, La@C 82 , was also adsorbed on graphene, which acts as an electron donor. Upon optical illumination, for the Sc 3 N@C 80 –graphene hybrid, the photoinduced free holes are injected into graphene, increasing the hole carrier concentration in graphene, while the photoexcited electrons remain in Sc 3 N@C 80 ; this leads to a high photoresponsivity  of ∼10 9 A W −1 , detectivity D of ∼10 15 Jones, and external quantum efficiency EQE ∼ 10 9 % for the Sc 3 N@C 80 –graphene hybrid. This  is ∼10 times higher compared to other reports of quantum dot-graphene and few layer MoS 2 –graphene heterostructures. Similarly, for the La@C 82 –graphene hybrid,  ∼ 10 8 A W −1 , D ∼ 10 14 Jones, and EQE ∼ 10 6 % were achieved, with electrons being injected into graphene. The exceptional performance gains achieved with both types of hybrid structures confirms the potential of endohedrals to dope graphene for high performance optoelectronic devices using a facile and scalable fabrication process.  more » « less
Award ID(s):
1801317
PAR ID:
10172704
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry C
Volume:
8
Issue:
12
ISSN:
2050-7526
Page Range / eLocation ID:
3970 to 3981
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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