Surface photovoltage characterization of sol-gel derived Bi4Ti3O12 ferroelectric thin film on F-doped SnO2 conducting glass

(a) SPS of BiT film at different external voltages. (Inset: scheme of the structure of the photovoltaic cell.) (b) SPS of the BiT film with and without external poling. The poling was applied with a voltage of +1 V.