CC BY-NC-ND 4.0 UnportedNajafidehaghani, EmadGan, ZiyangGeorge, AntonyLehnert, TiborNgo, Gia QuyetNeumann, ChristofBucher, TobiasStaude, IsabelleKaiser, DavidVogl, TobiasHübner, UweKaiser, UteEilenberger, FalkTurchanin, Andrey2021-11-252021-11-252021https://oa.tib.eu/renate/handle/123456789/7482https://doi.org/10.34657/6529Lateral heterostructures of dissimilar monolayer transition metal dichalcogenides provide great opportunities to build 1D in-plane p–n junctions for sub-nanometer thin low-power electronic, optoelectronic, optical, and sensing devices. Electronic and optoelectronic applications of such p–n junction devices fabricated using a scalable one-pot chemical vapor deposition process yielding MoSe2-WSe2 lateral heterostructures are reported here. The growth of the monolayer lateral heterostructures is achieved by in situ controlling the partial pressures of the oxide precursors by a two-step heating protocol. The grown lateral heterostructures are characterized structurally and optically using optical microscopy, Raman spectroscopy/microscopy, and photoluminescence spectroscopy/microscopy. High-resolution transmission electron microscopy further confirms the high-quality 1D boundary between MoSe2 and WSe2 in the lateral heterostructure. p–n junction devices are fabricated from these lateral heterostructures and their applicability as rectifiers, solar cells, self-powered photovoltaic photodetectors, ambipolar transistors, and electroluminescent light emitters are demonstrated. © 2021 The Authors. Advanced Functional Materials published by Wiley-VCH GmbHenghttps://creativecommons.org/licenses/by-nc-nd/4.0/6205405302D deviceslateral heterostructureslight-emitting diodep–n junctiontransition metal dichalcogenides monolayersArticle