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In this work, we demonstrate direct van der Waals epitaxy of MoS₂–graphene heterostructures on a semiconducting silicon carbide (SiC) substrate under ultrahigh vacuum conditions. Angle-resolved photoemission spectroscopy (ARPES) measurements show that the electronic structure of free-standing single-layer (SL) MoS₂ is retained in these heterostructures due to the weak van der Waals interaction between adjacent materials. The MoS₂ synthesis is based on a reactive physical vapor deposition technique involving Mo evaporation and sulfurization in a H₂S atmosphere on a template consisting of epitaxially grown graphene on SiC. Using scanning tunneling microscopy, we study the seeding of Mo on this substrate and the evolution from nanoscale MoS₂ islands to SL and bilayer (BL) MoS₂ sheets during H₂S exposure. Our ARPES measurements of SL and BL MoS₂ on graphene reveal the coexistence of …