Interface Energy-Level Reorganization for Efficient Perovskite γ-Ray Detectors

Area of Science:

• Materials Science
• Nuclear Instrumentation
• Solid-State Physics

Background:

• Metal halide perovskites show potential for gamma-ray (γ-ray) detection.
• High-resolution γ-ray spectroscopy is hindered by leakage currents degrading energy signals.

Purpose of the Study:

• To suppress leakage current in perovskite γ-ray detectors through surface ligand engineering.
• To improve the energy resolution and stability of perovskite-based γ-ray detectors.

Main Methods:

• Engineered perovskite crystal surfaces by anchoring strong dipole ligands.
• Manipulated surface energy levels to create a higher contact barrier and reduce leakage current.
• Fabricated and tested perovskite detectors under bias voltage and continuous electric fields.

Main Results:

• Leakage current reduced by an order of magnitude to 44 nA/cm² at -100 V.
• Achieved 3.9% energy resolution for 511 keV γ-rays at room temperature.
• Demonstrated stable energy resolution for over 300 minutes, resolving complex γ-spectra.

Conclusions:

• Surface ligand engineering effectively minimizes leakage current in perovskite detectors.
• The improved detectors offer high-resolution γ-ray spectroscopy with enhanced stability and longevity.
• This work advances perovskites as a leading material for next-generation γ-ray detection applications.