Temperature-Dependent Interplay between Structural and Charge Carrier Dynamics in CsMAFA-Based Perovskites

State-of-the-art triple cation, mixed halide perovskites are extensively studied in perovskite solar cells, showing very promising performance and stability. However, an in-depth fundamental understanding of how the phase behavior in Cs_0.05FA_0.85MA_0.10Pb(I_0.97Br_0.03)₃ (CsMAFA)...

Comparing the charge dynamics in MAPbBr3 and MAPbI3 using microwave photoconductance measurements

Perovskite-based solar cells have been rapidly developed, with record power conversion efficiencies now exceeding 25%. In order to rationally improve the efficiency of these devices, it is important to understand and quantify the dynamics of the excess charge carriers.

Crystallization Process for High-Quality Cs_0.15FA_0.85PbI_2.85Br_0.15Film Deposited via Simplified Sequential Vacuum Evaporation

Multiple-source thermal evaporation is emerging as an excellent technique to obtain perovskite (PVK) materials for solar cell applications due to its solvent-free processing, accurate control of stoichiometric ratio, and potential for scalability. Nevertheless, the currently reported layer-by-layer deposition approach is afflicted by long...

Charge distribution in CsFAPbI₃ spatially resolved by scanning microwave impedance microscopy

Metal-halide perovskites deposited by wet-chemical deposition have demonstrated great potential for various electronic applications, including solar cells. A remaining question is how light-induced excess charges become distributed over such polycrystalline material. Here, we examine the local conductive properties of MAPbI₃ and...

Charge Carrier Dynamics in Co-evaporated MAPbI₃with a Gradient in Composition

Co-evaporation of metal halide perovskites by thermal evaporation is an attractive method since it does not require harmful solvents and enables precise control of the film thickness. Furthermore, the ability to manipulate the Fermi level allows the formation of a graded homojunction, providing interesting opportunities to improve the charge...

Predicting Solar Cell Performance from Terahertz and Microwave Spectroscopy

Mobilities and lifetimes of photogenerated charge carriers are core properties of photovoltaic materials and can both be characterized by contactless terahertz or microwave measurements. Here, the expertise from fifteen laboratories is combined to quantitatively model the current-voltage characteristics of a solar cell from such measurements....

Traps in the spotlight: How traps affect the charge carrier dynamics in Cs₂AgBiBr₆ perovskite

Suitable optoelectronic properties of lead halide perovskites make these materials interesting semiconductors for many applications. Toxic lead can be substituted by combining monovalent and trivalent cations, such as in Cs₂AgBiBr₆. However, efficiencies of Cs₂AgBiBr₆-based photovoltaics are still...

How Deep Hole Traps Affect the Charge Dynamics and Collection in Bare and Bilayers of Methylammonium Lead Bromide

Wide-band-gap perovskites such as methylammonium lead bromide (MAPB) are promising materials for tandem solar cells because of their potentially high open-circuit voltage, which is yet still far below the maximum limit. The relatively short charge-carrier lifetimes deduced from time-resolved photoluminescence (TRPL) measurements seem in...

Analytical approach for determining the mean water level profile in an estuary with substantial fresh water discharge

The mean water level in estuaries rises in the landward direction due to a combination of the density gradient, the tidal asymmetry, and the backwater effect. This phenomenon is more prominent under an increase of the fresh water discharge, which strongly intensifies both the tidal asymmetry and the backwater effect. However, the interactions...