“…Therefore, various alternative material solutions are sought. To date, the highest attention has been paid to Bi 2 O 3 [ 7 , 8 , 9 , 10 ] followed by TiO 2 [ 11 , 12 , 13 , 14 ], Fe 2 O 3 [ 15 , 16 , 17 ] or WO 3 [ 18 , 19 , 20 , 21 , 22 ]. Bismuth oxide exhibits similarly high radiation attenuating properties regarding gamma radiation as lead, but is considered non-toxic.…”