Hybrid halide perovskite neutron detectors

Area of Science:

• Materials Science
• Nuclear Instrumentation
• Solid-State Physics

Background:

• Hybrid halide perovskites are effective detectors for X-rays and gamma rays due to their high sensitivity and ease of use.
• Fast and easy detection of high-energy radiation is crucial for applications in biomedicine, industry, and homeland security.

Purpose of the Study:

• To demonstrate the efficient detection of thermal neutrons using a methylammonium lead tri-bromide perovskite single crystal (CH3NH3PbBr3 SC) coupled with a Gadolinium (Gd) foil.
• To investigate the underlying detection mechanism and optimize detector performance.

Main Methods:

• Assembling a CH3NH3PbBr3 SC with a Gd foil to convert absorbed neutrons into gamma rays.
• Measuring the induced electric current generated by photo-carriers in the perovskite SC.
• Investigating the effects of beam size, bias voltage, and conversion distance.
• Utilizing carbon electrodes for stable charge extraction.
• Testing alternative conversion layers like borated polyethylene, Gd grains, and Gd2O3 pellets.
• Employing Monte Carlo N-Particle (MCNP) code for quantitative confirmation of the detection mechanism.

Main Results:

• The Gd foil efficiently converts thermal neutrons into gamma rays, which are then detected by the CH3NH3PbBr3 SC.
• The induced photocurrent is measurable and correlates with neutron radiation intensity.
• Performance was optimized by investigating various parameters and conversion materials.
• Carbon electrodes ensured stable and efficient charge extraction.

Conclusions:

• The Gd-perovskite SC assembly provides an efficient method for thermal neutron detection.
• This approach leverages the properties of hybrid halide perovskites for a new class of radiation detectors.
• The findings have potential implications for radiation monitoring in diverse fields.