Charge Carrier Dynamics of Organic Cation-Treated Perovskites Probed with Time-Resolved Microwave Conductivity

Metal halide perovskites have emerged as a set of promising optoelectronic materials benefiting from their outstanding optoelectronic proper-ties and unprecedented success in photovoltaics. Recent studies have suggested that mixing lower-dimensional A-site cations within perovskites helps mitigate this environmental and phase instability for 3D perovskites. However, the charge carrier transport properties in mixed 2D/3D perovskites are still not fully understood. In this work, charge carrier mobilities and recombination rate constants in perovskite thin films were analyzed with transient time-resolved microwave conductivity and time-resolved photoluminescence. It was found that upon large-cation treatment of 3D perovskites, charge carrier transport and radiative recombination efficiency were enhanced by the passivation of surface defects, which is evidenced by the decay dynamics of charge carriers.

Automated summary

Metal halide perovskites are promising optoelectronic materials with excellent properties and success in photovoltaics. Recent studies have shown that mixing lower-dimensional cations within perovskites can help improve their stability. However, the charge carrier transport properties in mixed 2D/3D perovskites are still not fully understood.