Perovskite Core-Shell Nanowire Transistors: Interfacial Transfer Doping and Surface Passivation

Area of Science:

• Materials Science
• Nanoscience
• Electronics

Background:

• Halide perovskite electronics show promise but are hindered by poor charge transport and stability.
• Cesium lead bromide perovskite (CsPbBr3) nanowires (NWs) are a key material for low-dimensional devices.
• Surface functionalization is crucial for overcoming limitations in perovskite materials.

Purpose of the Study:

• To achieve effective surface charge transfer doping of CsPbBr3 nanowires using molybdenum trioxide (MoO3).
• To investigate the impact of MoO3 surface functionalization on charge transport and stability.
• To evaluate the photodetection performance of the modified perovskite nanowires.

Main Methods:

• Vapor-liquid-solid (VLS) growth of single-crystalline CsPbBr3 nanowires.
• Surface functionalization of CsPbBr3 NWs with a 10 nm thick MoO3 shell.
• Fabrication of NW devices for field-effect mobility and photodetection measurements.

Main Results:

• Achieved a 15x increase in field-effect hole mobility (μh) from 1.5 to 23.3 cm2/(V s) after MoO3 deposition.
• Demonstrated superior photodetection performance with responsivity (R) up to 2.36 × 10^3 A/W and EQE > 5.48 × 10^5%.
• The MoO3 shell provided excellent surface passivation, enhancing air stability by minimizing water and oxygen diffusion.

Conclusions:

• Surface charge transfer doping via MoO3 is an effective strategy to boost charge transport in CsPbBr3 NWs.
• The enhanced mobility and stability pave the way for high-performance perovskite field-effect transistors (FETs).
• This approach enables the development of stable, low-dimensional halide perovskite devices for optoelectronic applications.