Polycrystalline MAPbI₃ AC-bias direct x-ray detectors for 3D reconstruction

Area of Science:

• Materials Science
• Physics
• Medical Imaging

Background:

• Metal halide perovskites exhibit high sensitivity for direct X-ray detection via direct current (DC) signals.
• DC bias in perovskite X-ray detectors causes ion migration, leading to signal instability and reduced operational lifespan.
• Existing perovskite X-ray detectors face challenges in achieving consistent signal output and long-term stability.

Purpose of the Study:

• To develop a novel capacitance signal-based imaging strategy for metal halide perovskite X-ray detectors.
• To mitigate ion migration and nonlinear responses in perovskite X-ray detectors using an alternating current (AC) bias.
• To establish a stable and high-resolution X-ray imaging technique with enhanced signal reliability.

Main Methods:

• Implemented an alternating current (AC) bias instead of direct current (DC) bias to operate metal halide perovskite X-ray detectors.
• Developed a capacitance signal-based imaging strategy to quantify X-ray dose rate.
• Utilized a single-pixel detector for achieving three-dimensional (3D) internal structure reconstruction.

Main Results:

• Successfully suppressed ion migration and eliminated nonlinear responses in perovskite X-ray detectors.
• Established a quantitative correlation between capacitance changes and X-ray dose rate.
• Achieved stable, high-resolution 3D X-ray imaging and internal structure reconstruction using a single-pixel detector.

Conclusions:

• The capacitance signal-based imaging strategy effectively overcomes the limitations of DC bias-induced ion migration in metal halide perovskites.
• This AC bias approach enhances signal reliability and enables stable, high-resolution X-ray imaging and computed tomography.
• The findings present a viable pathway for the commercialization of cost-effective, high-performance perovskite-based X-ray imaging systems.