Highly Emissive Lanthanide-Based 0D Metal Halide Nanocrystals for Efficient Ultraviolet Photodetector

Area of Science:

• Materials Science
• Nanotechnology
• Solid-State Physics

Background:

• Lanthanide-based 0D metal halides are gaining traction for optoelectronic devices like LEDs and photodetectors.
• Cesium cerium chloride (Cs3CeCl6) is a promising material, but its properties can be further optimized.

Purpose of the Study:

• To introduce lead-free 0D gadolinium-alloyed Cs3CeCl6 nanocrystals (NCs) for optoelectronic applications.
• To investigate the impact of Gd3+ incorporation on the optical, structural, and stability properties of Cs3CeCl6 NCs.
• To evaluate the performance of these alloyed NCs in ultraviolet photodetectors (UVPDs).

Main Methods:

• Synthesis of Gd3+-alloyed Cs3CeCl6 (CCGC) nanocrystals.
• Characterization of structural and optical properties, including photoluminescence quantum yield (PLQY).
• Density functional theory (DFT) calculations for structural analysis.
• Fabrication and testing of UVPDs using CCGC NCs as the active layer.

Main Results:

• Gd3+ incorporation significantly increased PLQY from 57% to 96% and enhanced phase and chemical stability.
• DFT confirmed the beneficial effect of Gd3+ in the Cs3Ce1-xGdxCl6 alloy system.
• CCGC NCs exhibited excellent UVPD performance, particularly at 20% Gd3+ concentration, with high detectivity (7.938 × 10^11 Jones) and responsivity (0.195 A W^-1) at 310 nm.

Conclusions:

• Gd3+-alloyed Cs3CeCl6 NCs are promising lead-free materials for optoelectronics.
• The enhanced optical and stability properties make them suitable for advanced UVPDs.
• This work opens avenues for developing novel lanthanide-based materials for next-generation optoelectronic devices.