Perovskite crystals can be used as nuclear radiation detectors, scientists have found.
The authors of the new work have made a detector based on perovskite, which detects leaks at nuclear power plants.
Perovskite crystals are used in scientific experiments due to their property – to make electricity from photons. But the researchers were able to reverse this process and tune the perovskites so that they trap neutrons: thanks to this, they created a detector for leaks of radioactive materials.
Perovskite is a relatively rare mineral of calcium titanate for the Earth’s surface, the crystals of which are pseudo-cubic. It is used in solar cells. But they can be applied to more than just solar cells: the same trapping mechanism that perovskites have can be used for other types of subatomic particles, such as neutrons.
Free neutrons come from nuclear reactions, so a perovskite device can capture different concentrations of neutrons to find leaks in nuclear power plants or among radioactive materials that are improperly stored or transported.
The authors of the new study used a compound called methylammonium lead tribromide. They exposed it to a neutron source, and tiny electrical currents began to appear as a result. This happens because neutrons penetrate into the nuclei of the atoms of the crystal, exciting them and transferring them to a higher energy state. The process then quickly breaks down into gamma rays, which charge the perovskite and create a measurable current.
The final version of the detector looked like a perovskite crystal wrapped in gadolinium foil. As a result, it was possible to amplify the signal and even measure the direction and size of the neutron flux.