Low-temperature synthesis of Cs2BaBr4 microcrystals via Water-Assisted Solid-State Reaction for low-dose X-ray sensing

X-rays represent a significant milestone in medical science; however, it is crucial to monitor the amount of radiation absorbed by the human body. Repeated exposure to low-dose X-rays can pose severe health risks, including cancer. To develop an appropriate low-dose X-ray sensing material, we focused on cesium barium bromide (Cs₂BaBr₄), a ternary metal halide compound synthesized using the Water-Assisted Solid-State Reaction (WASSR) method. Previously, Cs₂BaBr₄ had only been synthesized through the Bridgman method. In this study, we report for the first time the preparation of Cs₂BaBr₄ microcrystals via the facile and cost-efficient WASSR method to investigate their low-dose X-ray sensing properties. Before coating the prepared microcrystals onto the BPW34 photodiode for X-ray sensing, we subjected them to various characterization studies, including Powder X-ray Diffraction, Thermogravimetric Analysis, Field Emission Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, High Resolution-Transmission Electron Microscopy, Ultraviolet-Diffuse Reflectance Spectroscopy, and Photoluminescence. Finally, we coated the synthesized Cs₂BaBr₄ microcrystals with oleic acid (OA) and oleylamine (OAm) on the BPW34 photodiode and examined their X-ray-induced photocurrent characteristics. Using OA and OAm as surfactants in different ratios yielded improved results for studying the low-dose X-ray sensing properties.