2D materials show outstanding properties that can bring many applications in different technological fields. However, their uses are still limited by production methods. In this context, antimonene is recently suggested as a new 2D material to fabricate different (opto)electronic devices, among other potential applications. This work focuses on optimizing the synthetic parameters to produce high-quality antimonene hexagons and their implementation in a large-scale manufacturing procedure. By means of a continuous-flow synthesis, few-layer antimonene hexagons with ultra-large lateral dimensions (up to several microns) and a few nanometers thick are isolated. The suitable chemical post-treatment of these nanolayers with chloroform gives rise to antimonene surfaces showing low oxidation that can be easily contacted with microelectrodes. Therefore, the reported procedure offers a way to solve two critical problems for using antimonene in many applications: large-scale preparation of high-quality antimonene and the ability to set electrical contacts useful for device fabrication.