In collaboration with Nanjing Tech University, we have demonstrated a phase and heterostructure engineering on ultrathin perovskites, through the reversible cation exchange of hybrid perovskites and efficient surface functionalization of low-dimensional materials. A perovskite nanosheet can be combined with other 2D materials form lateral and vertical heterostructures, giving rise to strong interfacial coupling and interesting optical properties. In this work, Mike has used DFT calculations to determine the energy levels of MAPbI3 and MoS2 and construct the band alignment of the heterostructures. Our calculations show depending the surface termination of the perovskites, two distinctly different alignments can be obtained.

The work is recently accepted for publication by Advanced Materials. It shows the flexible design of hybrid perovskites and their integration with diverse 2D materials offer many possibilities to discover new properties and functionalities, therefore open an attractive route for the search and control of two-dimensional materials.