Polycrystalline films of bismuth triiodide are used as beta direct and digital detectors for medical imaging applications. Bismuth(III) iodide is used as an ice nucleant. It is also used in electron microscopy to reveal synapses. Addition of bismuth triiodide has been shown to improve the glass forming ability and thermal stability of Ge-Te-BiI(3) chalcogenide glasses. Solution-processable BiI3 nanosheets have been shown to exhibit the potential to be used as HTLs (Hole Transport Layer) in conventional OPV (organic photovoltaic) devices.
Iodine (20 g.) is ground with 45 g. of finely powdered Bi in a mortar and then rapidly placed in a retort. The mixture is heated until reaction begins. At the end of the reaction, a stream of CO3 is passed through the warm retort to remove unreacted iodine. The iodide is then sublimed in a stream of CO3. Smaller quantities can also be prepared by placing the mixture in a boat inserted into a Vycor tube, heating, and then subliming the Bil 3 in a CO3 stream.
