Roles of oxygen vacancy and ferroelectric polarization in photovoltaic effects of BiFeO₃ based devices

In this work, with BiFeO3 (BFO) and corresponding photovoltaic devices obtained by spin coating, deep insights into the role of polarization and oxygen vacancy in photovoltaic performance. Doped La and Sr present an opportunity to implement quite diverse effect on ferroelectric and photovoltaic properties of BFO based devices film. It can be concluded that Sr-doped ions could meliorate the photovoltaic performance of BFO based devices by introducing more oxygen vacancies with the highest open circuit voltage. The effect of electric field on photovoltaic response can be improved in La-doped device by enhancing the ferroelectric property. These results will facilitate the understanding of mechanisms in ferroelectric photovoltaic devices with tunable performance and advance new many-sided route for exploring enhanced photovoltaic properties based on ferroelectric films.