2D Materials have attracted widespread attention due to their extraordinary electronic, optical and mechanical properties. They possess strong in‐plane chemical bonds between their constituent atoms and weak interaction between the layers. In this seminar, I will talk about our recent results on phosphorene and transition metal dichalcogenides (MoS2 and MoSe2). Phosphorene, a mono-layer of elemental phosphorus, has recently emerged as a sensational 2D semiconductor which shows thickness tuneable band-gap in the 0.3-2.0 eV range, high charge carrier mobility (~ 1,000 cm2 V −1 s −1 ) and ION/IOFF ratio (>105 ). However, the application of phosphorene is thwarted by its poor stability under ambient conditions. We have shown that phosphorene can be stabilized under ambient conditions by chemical functionalization without causing loss to its physical properties. The functionalized phosphorene exhibits good dispersibility in water as well as superior and robust HER (H2 evolution reaction) activity compared to that of the pristine sample. Covalently cross-linked 2D/2D nanocomposites of phosphorene with MoS2 and MoSe2 show excellent photo- and electro-chemical HER activity. I will also discuss 2D/0D nanocomposite of MoS2 with Fe3O4 formed via organic linkers. The MoS2/Fe3O4 nanocomposite is a quick and easy recoverable HER catalyst.