Charge Carrier Dynamics in Halide Perovskite Materials

Halide perovskites have emerged as a class of semiconductors distinguished by their remarkable optoelectronic properties, combining solution processability with high charge‐carrier mobilities, long diffusion lengths and tunable bandgaps. At the heart of device performance in photovoltaics, light-emitting diodes and photodetectors lies the behaviour of photoexcited electrons and holes as they thermalise, scatter and recombine. Carrier dynamics in these materials are governed by interactions with lattice vibrations, defect states and intercarrier scattering, which together determine lifetimes, cooling rates and recombination pathways. The presence of large polarons and dynamic disorder of the lead‐halide lattice modulates electron–phonon coupling, giving rise to phenomena such as hot‐phonon bottlenecks and slowed carrier cooling. These mechanisms underlie proposals for hot‐carrier solar cells capable of exceeding conventional efficiency limits, as well as strategies to suppress non‐radiative decay and enhance charge extraction. Understanding and controlling these ultrafast processes is essential for optimising device architecture and material composition, paving the way to perovskite-based technologies with improved stability, efficiency and spectral response.

Research from Nature Portfolio

Studies have meticulously quantified the coupling between carriers and longitudinal optical phonons, revealing that Fröhlich interactions dominate scattering near room temperature and set upper bounds on mobility. Investigations into hot‐carrier cooling have demonstrated that energy relaxation is mediated by a phonon bottleneck, where delayed longitudinal optical phonon emission and suppression of anharmonic decay pathways prolong carrier cooling times. Comparative analyses across different A-site cations and halide compositions show that organic cations enhance phonon up‐conversion, further slowing cooling through overlapping vibrational modes. Together, these findings resolve key debates on the roles of large polarons, phonon dynamics and Auger heating in retarding carrier thermalisation, and they establish design rules for engineering lattice dynamics to harness hot carriers in next‐generation devices.

Charge Carrier Dynamics in Halide Perovskite Materials publication trend

The graph below shows the total number of articles in charge carrier dynamics in halide perovskite materials across all publications each year (not limited to Nature Index journals).

Technical terms

Charge carrier mobility: The measure of how rapidly electrons or holes traverse a semiconductor under an applied electric field.

Hot‐phonon bottleneck: A phenomenon in which emitted optical phonons are reabsorbed by carriers, slowing their cooling and prolonging high‐energy populations.

Fröhlich interaction: The long‐range coupling between charge carriers and longitudinal optical phonons in polar crystals, a key determinant of scattering rates.

Polaron: A quasiparticle comprising a charge carrier together with its accompanying lattice distortion, which alters effective mass and mobility.

Quantum confinement: The modification of electronic and phononic properties when charge carriers are restricted to dimensions comparable to their de Broglie wavelength, as in two‐dimensional perovskites.

References

1. Structurally Flexible 2D Spacer for Suppressing the Electron–Phonon Coupling Induced Non-Radiative Decay in Perovskite Solar Cells. Nano-Micro Letters (2024).
2. Carrier Cooling in Lead Halide Perovskites: A Perspective on Hot Carrier Solar Cells. ACS Energy Letters (2023).
3. Thermalization and relaxation mediated by phonon management in tin-lead perovskites. Light: Science & Applications (2023).
4. Electron–phonon coupling in hybrid lead halide perovskites. Nature Communications (2016).
5. Lead halide perovskites: Crystal-liquid duality, phonon glass electron crystals, and large polaron formation. Science Advances (2017).
6. Extended carrier lifetimes and diffusion in hybrid perovskites revealed by Hall effect and photoconductivity measurements. Nature Communications (2016).
7. Hot carrier cooling mechanisms in halide perovskites. Nature Communications (2017).
8. Acoustic-optical phonon up-conversion and hot-phonon bottleneck in lead-halide perovskites. Nature Communications (2017).