2D Monolayer of the 1T’ Phase of Alloyed WSSe from Colloidal Synthesis

We explore the colloidal growth of monolayers of WSSe alloy in their 1T' phase with various Se contents. We develop a synthetic procedure leading to reduced aggregation of the flakes. The presence of a narrow band-gap close to the top of the valence band has been evidenced combining photoemission spectroscopy and density functional theory (DFT). The electronic structure is weakly affected by the variation of the alloy content and atomic ordering. μ-Raman spectroscopy and STEM are used to confirm the obtained 1T' phase, while simulations of the Raman spectra suggest contribution from both the S and Se atoms in the Raman spectra. Finally, we use electronic transport and photoconduction and reveal a short coherence length, consistent with the defective nature of the flakes.