Growth difficulties and growth of crack free Eu2+ activated KSr2I5 scintillator single crystal by vertical bridgman-stockbarger technique for radiation detection applications

[Display omitted] •The starting materials were purifying using melt technique and zone refining.•12–20 mm diameter KSr2I5:Eu2+ crystal was grown via Bridgman-Stockbarger technique.•The radioluminescence emission peak was monitored at 448 nm.•The energy resolution of KSr2I5:Eu2+ crystal was 3.5 % for 137Cs energy is 662 keV. Europium activated potassium strontium iodide (KSr2I5:0.5Eu2+) compound was synthesized and refined by indigenous zone-refinement experimental set-up. The impurities that are insoluble in the KSr2I5:Eu2+ compound was filtered by using a specifically programmed dual chamber quartz ampoule with frit filter method. Temperature profile of this in-house built vertical transparent Bridgman-Stockbarger technique growth furnace is optimized to grow quality single crystals of KSr2I5:Eu2+. From the photoluminescence emission spectrum a typical 4f6 5d1 – 4f7 transition is observed for a broad emission peak at 432 nm whereas a broad emission peak at 448 nm was obtained from the X-ray excited radioluminescence spectrum. The gamma ray spectrometer was administered to detect the scintillation properties of the grown crystal. The scintillation decay time was calculated for the KSr2I5:Eu2+ crystal wherein the energy resolution under 137Cs sealed gamma source is found to be 3.5 % at 662 KeV.