From 2D to 1D Electronic Dimensionality in Halide Perovskites with Stepped and Flat Layers Using Propylammonium as a Spacer.

Two-dimensional (2D) hybrid halide perovskites are promising in optoelectronic applications, particularly solar cells and light-emitting devices (LEDs), and for their increased stability as compared to 3D perovskites. Here, we report a new series of structures using propylammonium (PA), which results in a series of Ruddlesden-Popper (RP) structures with the formula (PA)(MA)PbI ( = 3, 4) and a new homologous series of "step-like" (SL) structures where the PbI octahedra connect in a corner- and face-sharing motif with the general formula (PA)(MA)PbI ( = 2, 3, 4). The RP structures show a blue-shift in bandgap for decreasing (1.

Does Rashba splitting in CHNHPbBr arise from 2 × 2 surface reconstruction?

As a result of early theoretical predictions, evidence for the Rashba or Dresselhaus effect in hybrid perovskites has recently attracted several experimental investigations, motivated by possible applications in spin-orbitronics. For instance, a large Rashba splitting has recently been reported for the (001) surface of CH3NH3PbBr3. This effect is forbidden in the bulk material since both low-temperature and room-temperature crystal structures present inversion symmetry.

Composite Nature of Layered Hybrid Perovskites: Assessment on Quantum and Dielectric Confinements and Band Alignment.

Layered hybrid organic-inorganic perovskites (HOPs) have re-emerged as potential technological solutions for next-generation photovoltaic and optoelectronic applications. Their two-dimensional (2D) nature confers them a significant flexibility and results in the appearance of quantum and dielectric confinements. Such confinements are at the origin of their fascinating properties, and understanding them from a fundamental level is of paramount importance for optimization.