Dynamic study of phase transition in Bi2O3 epitaxial film induced by electrolyte gating

Electrolyte gating with ionic liquids has been broadly applied in various fields in recent years. However, it remains under debate since defect-controlling and electrochemical doping are conventionally disputed to interpret the corresponding mechanism. In this work, we provide the synergistic mechanism that oxygen vacancy migration and element-doping together drive the formation of metallization. The prepared Bi2O3 films experienced insulator-metal transition and structural transformation by field-induced ionic liquid. The consequent structural transition in the Bi2O3 film was dynamically monitored by XRD, and the results indicated that an extraordinary metal Bi phase was formed during the electrolyte gating process, which was further verified by HR-TEM and XPS. Our current findings will boost the development of electrolyte gating and bring insight into other metal oxides in ionic liquid gating experiment.Electrolyte gating with ionic liquids has been broadly applied in various fields in recent years. However, it remains under debate since defect-controlling and electrochemical doping are conventionally disputed to interpret the corresponding mechanism. In this work, we provide the synergistic mechanism that oxygen vacancy migration and element-doping together drive the formation of metallization. The prepared Bi2O3 films experienced insulator-metal transition and structural transformation by field-induced ionic liquid. The consequent structural transition in the Bi2O3 film was dynamically monitored by XRD, and the results indicated that an extraordinary metal Bi phase was formed during the electrolyte gating process, which was further verified by HR-TEM and XPS. Our current findings will boost the development of electrolyte gating and bring insight into other metal oxides in ionic liquid gating experiment.