Real-Time Structural Dynamics at the 3D/2D Perovskite Interface in CsPbBr₃/PEA₂PbBr₄ Nano-heterostructures

Area of Science:

• Materials Science
• Solid-State Physics
• Nanotechnology

Background:

• Three-dimensional (3D) and two-dimensional (2D) perovskites offer exceptional optoelectronic properties and stability.
• Understanding the fundamental physics and dynamics at 3D/2D perovskite interfaces is crucial but remains limited.

Purpose of the Study:

• To investigate the photoluminescence (PL) properties of 3D/2D perovskite nano-heterostructures.
• To elucidate the dynamics and structural changes occurring at the 3D/2D interfaces under light excitation.

Main Methods:

• Utilized fluorescence microspectroscopy to study CsPbBr3/PEA2PbBr4 3D/2D nano-heterostructures.
• Employed in situ PL spectral analysis to observe structural phase evolution and dynamics at room temperature.

Main Results:

• Identified new quasi-2D PEA2CsPb nBr3+1 phases at the 3D/2D interface.
• Observed reversible structural restructuring driven by layer-by-layer cation diffusion on a second timescale.
• Demonstrated light-induced reversible spectral shifts indicating dynamic interface changes.

Conclusions:

• The reversible restructuring optimizes quasi-2D phase distribution for efficient energy transfer from 2D to 3D perovskite phases.
• Provides fundamental insights into controlling energy flow at 3D/2D perovskite interfaces.
• Highlights potential for next-generation optoelectronic device applications.