Study of BiFeO3 thin film obtained by a simple chemical method for the heterojunction-type solar cell design

Abstract Polycrystalline BiFeO3 (BFO) films of different thickness were synthesized by a 2-methoxyethanol (acid)-free simple chemical method. A rhombohedral-type pure phase with a crystallite size less than 18.8 nm was obtained. SEM micrographs showed that BFO has a flat and homogeneous morphology when it was deposited on different semiconductor substrates (ZnO, Ni doped ZnO, and CdS). The highest roughness value (8.6 nm) was observed when BFO was deposited on CdS. The optical response showed that the optical band gap slightly changes as thickness increases. The photovoltaic response of the BFO film was assessed employing different solar cell architectures (p-BFO-n and BFO-n). The results showed that the solar cell based on the Ag/PbS/BFO/CdS/FTO/glass structure presented a short-circuit current density of J S C = 239.6 μ A / c m 2 and a power conversion efficiency of η = 7.65 × 10 − 3 % . Photoelectrochemical and ferroelectric measurements were employed to explain the photovoltaic response.