Ultrafast charge transfer dynamics pathways in two-dimensional MoS2–graphene heterostructures: a core-hole clock approach

• DOI: 10.1039/c7cp06283d
• Publication Date: 2017-10-16T08:35:00Z
• Authors: Yunier Garcia-Basabe; Alexandre R. Rocha; Flávio C. Vicentin; Cesar E. P. Villegas; Regiane Nascimento; Eric C. Romani; Emerson C. de Oli...; Guilhermino J. M....; Shisheng Li; Goki Eda; Dunieskys G. Larrude
• Keywords: Attosecond

Two-dimensional van der Waals heterostructures are attractive candidates for optoelectronic nanodevice applications. The charge transport process in these systems has been extensively investigated, however the effect of coupling between specific electronic states on transfer is not completely established yet. Here, interfacial (CT) MoS2/graphene/SiO2 heterostructure investigated from static and dynamic points view. Static CT MoS2-graphene interface was elucidated by an intensity quenching, broadening a blueshift photoluminescence peaks. Atomic state-specific dynamics femtosecond timescale characterized using core-hole clock approach S1s lifetime as internal clock. We demonstrate that electron pathway MoS2/SiO2 mainly due to S3p-Mo4d forming Mo-S covalent bond MoS2 layer. For heterostructure, we identify, with support density functional calculations, new pathways arise high empty graphene conduction band. latter makes time MoS2/graphene/SiO2/Si twice fast MoS2/SiO2/Si sample. Our results show ultrafast delocalization dependent properties each involved 2D material, creating opportunities modulate their properties.