A molecular sieve boosts perovskite stability
Highly efficient and stable perovskite solar cells are fabricated by introducing a molecular sieve which finely controls the 2D/3D heterointerface reactions.
energy↗
Engineering topics
Grancini, Giulia
Publications and source records attributed to Grancini, Giulia.
2D Phase Formation on 3D Perovskite: Insights from Molecular Stiffness
Not Available
2D/3D perovskites↗
Effect of Crystallite Size on the Flexibility and Negative Compressibility of Hydrophobic Metal–Organic Frameworks
Flexible nanoporous materials are of great interest for applications in many fields such as sensors, catalysis, material separation, and energy storage. Of these, metal–organic frameworks (MOFs) are the most explored thus far. However, tuning their flexibility for a particular application remains challenging. In this work, we explore the effect of the exogenous property of crystallite size on the flexibility of the ZIF-8 MOF. By subjecting hydrophobic ZIF-8 to hydrostatic compression with water, the flexibility of its empty framework and the giant negative compressibility it experiences during water intrusion were recorded via in operando synchrotron irradiation. It was observed that as the crystallite size is reduced to the nanoscale, both flexibility and the negative compressibility of the framework are reduced by ~25% and ~15%, respectively. These results pave the way for exogenous tuning of flexibility in MOFs without altering their chemistries.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Uncovering temperature-dependent exciton-polariton relaxation mechanisms in hybrid organic-inorganic perovskites
Hybrid perovskites have emerged as a promising material candidate for exciton-polariton (polariton) optoelectronics. Thermodynamically, low-threshold Bose-Einstein condensation requires efficient scattering to the polariton energy dispersion minimum, and many applications demand precise control of polariton interactions. Thus far, the primary mechanisms by which polaritons relax in perovskites remains unclear. In this work, we perform temperature-dependent measurements of polaritons in low-dimensional perovskite wedged microcavities achieving a Rabi splitting of ℏΩ Rabi = 260 ± 5 meV. We change the Hopfield coefficients by moving the optical excitation along the cavity wedge and thus tune the strength of the primary polariton relaxation mechanisms in this material. We observe the polariton bottleneck regime and show that it can be overcome by harnessing the interplay between the different excitonic species whose corresponding dynamics are modified by strong coupling. This work provides an understanding of polariton relaxation in perovskites benefiting from efficient, material-specific relaxation pathways and intracavity pumping schemes from thermally brightened excitonic species.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗