High-Luminescence and Submillimeter-Scale MoS<sub>2</sub> Monolayer Growth Using Combinational Phase Precursors via Chemical Vapor Deposition
Ary Anggara Wibowo, Mike Tebyetekerwa, Anh Dinh Bui, Felipe Kremer, Sandra Elizabeth Saji, Zongyou Yin, Yuerui Lu, Daniel Macdonald, Hieu T. Nguyen
Abstract
We successfully synthesize high-luminescence and submillimeter-scale monolayers of molybdenum disulfide (MoS2) employing a combinational phase precursor via a chemical vapor deposition (CVD) approach. First, sodium nitrate catalyst is demonstrated to assist the reaction equilibrium of a solid precursor CVD process, leading to an increased density and size of MoS2 monolayer flakes (∼120 μm). However, the monolayers’ photoluminescence intensity is significantly reduced due to the presence of excess residues. A suspension solution-based precursor is also tested using the optimized temperature, pressure, and catalyst from the solid precursor case, and it is found to also give a high density of uniform triangles with an average size of ∼80 μm. Finally, combining both precursor phases (combinational phase precursor) yields the largest monolayer flakes with an average size of ∼200 μm and the highest luminescence, with photoluminescence intensities being 1 order of magnitude higher than that of a standard mechanical exfoliated monolayer.