A general strategy for simultaneously generating surface-based supramolecular architectures on flat sp2-hybridized carbon supports and independently exposing on demand off-plane functionality with controlled lateral order is highly desirable in view of the noncovalent functionalization of graphene. Here, we address this issue by providing a versatile molecular platform [1] based on a library of new 3D Janus tectons able to form surface-confined supramolecular adlayers [2-3] in which it is possible to simultaneously (i) steer the 2D self-assembly on flat sp2-carbon based substrates [4] and (ii) tailor the external interface above the substrate by exposing a wide variety of small terminal chemical groups and functional moieties [1]. This approach is validated through the self-assembly study by scanning tunneling microscopy (STM) at the liquid-solid interface and molecular mechanics modeling. The successful self-assembly on graphene, together with the possibility to transfer the graphene monolayer onto various substrates, should considerably expend the domains of application of our functionalization strategy [1]. References: [1]. A. J. Attias et al. Angew. Chem. Int. Ed. 53, 10060, 2014. [2]. A. J. Attias et al Angew. Chem. Int. Ed. 50, 6562, 2011. [3]. A. J. Attias et al. Angew. Chem. Int. Ed. 47, 8412, 2008. [4]. A. J. Attias et al. Angew. Chem. Int. Ed., 46, 7404, 2007.