  Organic-inorganic halide perovskite solar cells have attracted much attention
due to their low-cost fabrication, flexibility, and high-power conversion
efficiency. More recent efforts show that the reduction from three- to
two-dimensions (2D) of organic-inorganic halide perovskites promises an
exciting opportunity to tune their electronic properties. Here, we explore the
effect of reduced dimensionality and heterostructure engineering on the
intrinsic material properties, such as energy stability, bandgap and transport
properties of 2D hybrid organic-inorganic halide perovskites using
first-principles density functional theory. We show that the energetic
stability is significantly enhanced by engineered perovskite heterostructures
that also possess excellent transport properties similar to their bulk
counterparts. These layered chemistries also demonstrate the advantage of a
broad range of tunable bandgaps and high-absorption coefficient in the visible
spectrum. The proposed 2D heterostructured material holds potential for
nano-optoelectronic devices as well as for effective photovoltaics.
