Chemical solution deposition of single phase BiFeO3 thin films on transparent substrates

The production of high quality BiFeO3 thin films on cost-effective transparent electrodes for visible light harvesting applications and devices remains a challenge. Here, we report the production of single-phase nanostructured BiFeO3 thin films via chemical solution deposition (CSD) on transparent conductive fluorine doped tin oxide FTO glass substrates. We show that the BiFeO3 is of high purity using a variety of analytical tools and that the as-obtained BiFeO3 thin films have a single grain single domain structure exhibiting ferroelectric switching under poling. The BiFeO3 samples show visible light absorption with a band gap of 2.7 eV under all processing conditions. By changing the annealing atmosphere it was possible to modify the photocurrent produced, which were (at 1.23 VNHE) 0.07 mA/cm2 (O2-annealed), 0.02 mA/cm2 (air-annealed) and 0.01 mA/cm2 (Ar-annealed). This indicates a change in the mobile carriers available. Our results show that it is possible to produce single phase BiFeO3 on a transparent conductive electrode system with controllable photoconductivity.