In this work, we have applied the OSS approach to study the thermal behavior and air stability of the I-BOPHY-I molecule when deposited on two metal surfaces, Au(111) and Ag(111), while extracting valuable comparative conclusions on the role played by the substrate (see Scheme 1). Particularly, the surface is not only used as catalytic support, but also provides adatoms that play a crucial role in the formation of these metalorganic nanostructures, as well as in their air stability. Using powerful surface analysis techniques, such as scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS), combined with first-principles theoretical DFT calculations, we structurally and chemically unveil the obtained nanostructures and their evolution when exposed to air. This work evidences the remarkable potential of OSS as a powerful tool for the construction of truly low-dimensional functional materials with technological interest and for the evaluation of the air stability of so-formed atomically-precise nanostructures.