▎ 摘　　要

BiI3 nucleation was performed by physical vapor transport (PVT) onto graphene covered TEM grids and graphene covered SiO2 substrates. Depositions were characterized by High Resolution Transmission Electron Microscopy (HR-TEM) and by Scanning Electron Microscopy with Field Emission Gun (SEM-FEG). Amorphous entities 2-3 nm in size were observed. They continue to be present even under the TEM beam and suffer rapid transformations between ordered and disordered structures. Given their size and amorphous character, we conclude that they are pre-nucleation entities, similar to the ones observed in solution and chemical vapor deposition (CVD) systems in the reports of non-classical nucleation research. The oriented attachment and amorphous addition of entities about 2-3 nm in size, giving larger ones of about 10-20 nm was observed. Nanoparticles interact among them by these non-classical mechanisms giving stable and oriented crystalline structures, in agreement with the different pathways reported in non-classical nucleation investigations. Platelets up to about 100-200 nm in size were also obtained, similar when imaged by TEM and by SEM. They give TEM clear Moire diagrams, similar to the ones obtained for other van der Waals superstructures. Non-classical nucleation here reported is similar to the one obtained for bismuth tri-iodide onto amorphous substrates, although the post growth - dictated by the crystalline substrate - is different, and gives van der Waals heterostructures. Results may be a valuable contribution to the development of a general theory for non-classical nucleation mechanisms in all kind of systems, and, as well, of 2D van der Waals materials and their applications.