A new study looks at conjugating 2D perovskites with optically active transition metal dichalcogenides (TMDs). The study can improve optoelectronic device performance and extend the functionalities of the perovskites.
Despite their structural differences, 2D perovskites and TMDs can form clean interfaces due to van der Waals interactions between the stacked layers. Using accurate first-principles calculations, the researchers show that the novel interface (band alignment) and transport properties are feasible in 2D perovskites and TMD heterostructures (widely tunable based on the constituents used).
To understand the interface properties accurately, the researchers created lattice-matched structures of the interfaces and explored their properties using highly memory-intensive computations on supercomputers.
The predicted type-II alignments with NIR/visible bandgaps can enable enhanced optical absorption at lower energies in specific systems. Furthermore, large band offsets and the possibility of interlayer excitons with lower dissociation energies can lead to easier interlayer separation of excited charge carriers between two materials.
It opens the door to higher photocurrents and improved solar cell efficiencies. The researchers also anticipate the development of type-I systems for recombination-based devices such as light-emitting diodes and type-III systems for tunneling transport. Furthermore, they demonstrate significant strain tolerance in 2D perovskites and TMD heterostructures required for flexible sensors.