Template-Assisted Synthesis of a Large-Area Ordered Perovskite Nanowire Array for a High-Performance Photodetector

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• One-dimensional (1D) organic-inorganic hybrid perovskite nanowires (NWs) offer excellent optical and electrical properties for optoelectronics.
• Air synthesis of perovskite NWs leads to defects due to water vapor sensitivity.
• Defects and grain boundaries degrade NW performance.

Purpose of the Study:

• To develop a method for fabricating high-quality CH₃NH₃PbBr₃ NWs with reduced defects.
• To investigate the structural and optical properties of the synthesized NWs.
• To evaluate the performance of NW-based photodetectors.

Main Methods:

• Template-assisted antisolvent crystallization (TAAC) method was employed.
• Acetonitrile vapor was introduced to sequester water and oxygen during synthesis.
• Structural characterization and transient absorption spectroscopy (TAS) were performed.

Main Results:

• The TAAC method produced CH₃NH₃PbBr₃ NW arrays with designable shapes, ordered alignment, and low crystal defects.
• Photodetectors demonstrated excellent light response with high responsivity (1.55 A/W) and detectivity (1.21 × 10¹² Jones).
• TAS revealed narrow absorption peaks, indicating minimal impurity-level transitions.

Conclusions:

• The TAAC method is an effective and simple strategy for achieving high-quality CH₃NH₃PbBr₃ NWs.
• These NWs show significant potential for advanced photodetection applications.
• Minimizing defects and controlling alignment are crucial for enhancing perovskite NW performance.