In the pursuit of a sustainable future, the last decade has seen a concerted effort in accelerating the discovery of materials for energy needs, thanks to a large extent to the Materials Genome Initiative. In this talk I will focus on few 2-dimensional materials which have captured our imagination. As with graphene, another common lubricant, molybdenum disulphide (MoS2) shows remarkable optical properties when peeled off as single sheet. I will show how defects and dopants in single-layer MoS2 transform its electronic structure so that it turn into a catalyst for CO hydrogenation. Even more interesting is the case of another 2D material, good old hexagonal boron nitride (h-BN), an vowed insulator. Defects, however, can transform it into a material that, on the one hand, captures and converts CO2 to value added products and, on the other, functions as a single photon emitter akin to NV centers in diamond. With a focus on electronic structural modulations of the local environment, I will draw comparisons with experimental observations made in collaborative work.