Temperature driven charge transfer process in quantum confined two-dimensional Mn-doped CsPbBr₃ perovskite...

Area of Science:

• Materials Science
• Solid State Physics
• Nanotechnology

Background:

• Cesium lead bromide (CsPbBr3) nanoplatelets are promising optoelectronic materials.
• Manganese (Mn2+) doping can tune the optical and electronic properties of CsPbBr3.
• Understanding charge carrier dynamics is crucial for device applications.

Purpose of the Study:

• To investigate the temperature-dependent charge transfer dynamics in Mn2+-doped CsPbBr3 nanoplatelets.
• To elucidate the role of defect states and exciton-phonon coupling in carrier transport.

Main Methods:

• Temperature-dependent transient absorption spectroscopy.
• Analysis of charge carrier trapping and de-trapping mechanisms.

Main Results:

• At 5 K, charge transfer is suppressed due to carrier trapping in defect states.
• At 300 K, efficient charge/energy transfer is observed.
• Strong exciton-phonon coupling facilitates carrier de-trapping at higher temperatures.

Conclusions:

• Temperature plays a critical role in controlling charge transfer in Mn2+-doped CsPbBr3 nanoplatelets.
• Defect states act as traps at low temperatures, while thermal energy promotes carrier mobility.
• Exciton-phonon coupling is essential for efficient charge transport at room temperature.