Halide Perovskites under Pressure: Accessing New Properties through Lattice Compression

Abstract

Lattice compression allows for systematic structural tuning without changing composition. Halide perovskites are a large and diverse family of solids, which have enormous potential for applications in energy capture, storage, and utilization. Notably, they have soft lattices and their photophysical and transport properties exhibit a large pressure response. In this Perspective, we highlight how pressure can alter their electronic landscapes, affect excited-state dynamics, and afford new structures not accessible through conventional syntheses. We further discuss how the insight we gain from high-pressure studies expands the scope of these versatile materials in current and future energy applications.

Pressure‐Induced Structural Evolution and Bandgap Optimization of Lead‐Free Halide Double Perovskite (NH4)2SeBr6

“…Moreover, the change in the bandgap as a function of pressure presents two turning points at 6.57 and 11.18 GPa, respectively, as shown in Figure 1d. Considering that the bandgap is determined by their crystalline structure, the two discontinuities in the bandgap may be related to the structural transitions . After releasing the pressure, the absorption of optical color and spectrum revert to their original state, which indicates reversible changes of the structures.…”

“…Considering that the bandgap is determined by their crystalline structure, the two discontinuities in the bandgap may be related to the structural transitions. [20,21] After releasing the pressure, the absorption of optical color and spectrum revert to their original state, which indicates reversible changes of the structures. These results clearly demonstrate that, the modulation of the optical properties of (NH 4 ) 2 SeBr 6 can be achieved by the application of pressure, which could further optimize its performance in solar energy conversion application.…”

Large lattice distortions and size-dependent bandgap modulation in epitaxial halide perovskite nanowires

“…Perovskites can accommodate an in-plane tensile or compressive strain also by octahedral tilting or rotation, perpendicular or parallel to the substrate (Fig. 6d) [66][67][68] .…”

Revealing Photoluminescence Modulation from Layered Halide Perovskite Microcrystals upon Cyclic Compression

“…This includes a diminished PL intensity, which eventually results in it being completely quenched due to a misalignment of the cations in the perovskite lattice, and a consequent loss of the long‐range ordering . Such reversible PL changes have been studied using 3D lead halide perovskite structures that have been subjected to high pressure conditions – with values ranging from a few GPa to ≈50 GPa – but PL modulation has not yet been observed under milder compression conditions (in the order of few MPa) which can be easily attained in a typical mechanical testing environment.…”