Preparation and photoconduction of rapidly quenched films in the Bi2O3-TiO2 system

摘要: The rapidly quenched films in the Bi2O3-TiO2 system (0 to 60% TiO2) were prepared using a twin-roller type apparatus. precipitated Bi2O3 solid solutions of different types composition ranges, with TiO2 contents 0 5, 7.5 10 and 12.5 40%, respectively. first solution had tetragonal structure β-form. second, though also crystallized structure, adopted disordered modification third was δ-form (defect fluorite structure). formation amorphous phase commenced 30% TiO2, became completely beyond 50% TiO2. showed certain instability decompose or transform into assemblage by annealing at higher temperatures (about 400 500° C, except 260° C for pure film). characterized high photoconductivity. photoconduction mechanism suggested be associated structural imperfection accompanied amount pentavalent bismuth ion.