Enhancing the Photovoltaic Performance of Directional-Growing Two-Dimensional Perovskites by Out-of-Plane...

Area of Science:

• Materials Science
• Solid-State Physics
• Photovoltaics

Background:

• Two-dimensional (2D) perovskites show promise for photovoltaics but face carrier transport limitations due to their quantum well structure.
• Overcoming in-plane carrier confinement typically requires inducing vertical orientation in photovoltaic devices.

Purpose of the Study:

• To investigate if out-of-plane polarization can overcome the carrier transport limitations in 2D perovskites.
• To evaluate the photovoltaic performance of 2D perovskite ferroelectrics with out-of-plane polarization.

Main Methods:

• Fabrication of photovoltaic devices using 4-(Aminomethyl)piperidiniumPbI4 (4-AMPI), a low-band-gap 2D perovskite ferroelectric, by annealing at various temperatures.
• Growth of 4-AMPI films along different crystal planes to study orientation effects.
• Measurement of photocurrent density under AM 1.5G irradiation for both parallel-grown and vertically grown films.

Main Results:

• Parallel-grown 4-AMPI films exhibited photocurrent density comparable to vertically grown films, demonstrating that out-of-plane polarization mitigates quantum well constraints.
• Photocurrent density of ferroelectric 4-AMPI was significantly higher than nonferroelectric 3-(aminomethyl)piperidiniumPbI4 (3-AMPI).
• Out-of-plane polarization in 4-AMPI enhances both carrier generation and transport.

Conclusions:

• Out-of-plane polarization effectively overcomes carrier limitations in 2D perovskites, enabling efficient charge transport.
• 2D molecular ferroelectrics with out-of-plane polarization are promising candidates for advanced photovoltaic device fabrication.