Fabrication of Cu₂O/γ-FeOOH heterojunction solar cells using electrodeposition

Abstract

Cu2O/γ-FeOOH heterojunction solar cells were fabricated using galvanostatic-potentiostatic electrodeposition methods. The γ-FeOOH films showed n-type conductivity with a band gap of 2.2 eV. The electrodeposited Cu2O/γ-FeOOH heterojunction exhibited photovoltaic characteristics with a short-circuit current density of 0.95 mA/cm2 and open-circuit voltage of 0.11 V. Using core-level spectroscopy, it was demonstrated that the Cu2O/FeOOH heterostructure exhibited a type II junction with a valence band offset of 0.8 eV. The conduction band minimum of Cu2O was predicted to be higher than that of γ-FeOOH by 0.7 eV. This finding indicates that the γ-FeOOH material can be regarded as a suitable hetero-partner of other p-type absorbers.