2017/03/31 by Alessandro Surrente, Dumitru Dumcenco, Zhuo Yang +11
Chemistry · Engineering · Materials Science · Physics and Astronomy · #2D Materials and Applications #Chemical vapor deposition #Chemistry #Computational chemistry #Condensed matter physics #Density functional theory #Fabrication #Graphene research and applications #Heterojunction #Materials science #Molecule #Monolayer #Nanotechnology #Optoelectronics #Perovskite Materials and Applications #Polarization (electrochemistry) #Vacancy defect #cond-mat.mes-hall #van der Waals force
paper · pdf · doi:10.1021/acs.nanolett.7b00904
Just accepted for publication in Nano Letters (http://pubs.acs.org/doi/abs/10.1021/acs.nanolett.7b00904)
openalex publication_date 2017/06/12 · arxiv created 2017/06/14 · arxiv updated 2017/06/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Monolayer transition metal dichalcogenides (TMDCs) grown by chemical vapor deposition (CVD) are plagued by a significantly lower optical quality compared to exfoliated TMDCs. In this work, we show that the optical quality of CVD-grown MoSe 2 is completely recovered if the material is sandwiched in MoS 2 /MoSe 2 /MoS 2 trilayer van der Waals heterostructures. We show by means of density functional theory that this remarkable and unexpected result is due to defect healing: S atoms of the more reactive MoS 2 layers are donated to heal Se vacancy defects in the middle MoSe 2 layer. In addition, the trilayer structure exhibits a considerable charge-transfer mediated valley polarization of MoSe 2 without the need for resonant excitation. Our fabrication approach, relying solely on simple flake transfer technique, paves the way for the scalable production of large-area TMDC materials with excellent optical quality.