I am working on a project where we want to do experiments on TMD monolayers (e.g. MoS2 or WS2). I recently found out that ACS Chemical is selling MoS2 monolayer films (https://www.acsmaterial.com/cvd-method-monolayer-mos2-film.html). I am a bit skeptical about the quality of these films since many people are actually working on this topic. Does anybody have experiences with these samples? For our experiments, we are interested in large area (at least 5x5mm) homogeneous large coverage monolayer TMDs with long luminescence lifetime and quantum yield. We are also working on producing our own samples, but it is tempting to simply buy them since the experiments alone are very complex.