A recent study conducted by the research team at Hefei Institutes of Physical Science of the Chinese Academy of Sciences, has introduced a new method for enhancing X-ray detection by incorporating out-of-phase CsPb 2 Br 5 perovskite into CsPbBr 3 bulk material.
"We achieved really good sensitivity for detecting X-rays (2.58×10 5 μC Gyair-1 cm -2 ), and a low detection limit (127.9 nGy air -1 )," said Prof. PAN Xu, who led the team, "We also integrated this technique with a thin-film transistor (TFT) plate to make X-ray images."
The relevant results were published in Advanced Functional Materials .
Metal halide perovskite is a promising material for detecting things like X-rays, offering better sensitivity and resolution than traditional detectors. Inorganic perovskite CsPbBr 3 has excellent environmental stability and unique high-temperature plasticity, rendering it particularly advantageous for X-ray detector and imaging applications. However, making single-crystal CsPbBr 3 is difficult and expensive, and polycrystalline CsPbBr 3 devices have low electron mobility, limiting their use in certain imaging systems.
In this study, scientists developed a new method called the Out-of-Phase Articulation Strategy (OPAS). They used OPAS to combine a special material called CsPb 2 Br 5 with another material called CsPbBr 3 . They made a mixture of these materials using a technique called high-energy mechanical ball milling. Adding CsPb 2 Br 5 didn't decrease the current baseline. Instead, it helped to speed up the movement of electrons and holes, which are important for detecting X-rays. This improvement was possible because CsPb 2 Br 5 created pathways for the electrons and holes to move more easily within CsPbBr 3 . Using this method, they achieved high sensitivity and spatial resolution for detecting X-rays without needing a lot of voltage.
In addition, the researchers put together CsPb 2 Br 5 /CsPbBr 3 on TFT backplanes to realize multi-pixel X-ray surface-array imaging. This proved that CsPbBr 3 material can be used for imaging. "It also gives us a new material system and design concept for using chalcocite in X-ray imaging," added YE.
This work shows that perovskites with the introduction of a 2D phase exhibit carrier transport effect and good long-term stability which making them promising candidates for commercial use.
Advanced Functional Materials