KCS

a-Fe2O3 has attracted attentions due to its good properties such as visible light absorption and stability.1 Powder type of Cu-doped hematite was synthesized and deposited on the FTO substrate. Purposely adjust the amount of Cu dopant (1, 2, 3, 5 mol% of Fe precursor) to study the effect of Cu doping. The photocatalytic activity of Cu-doped hematite was investigated by measuring photocurrent. The properties of the film were characterized by many methods such as XRD, TEM, SEM, IPCE, PEC, and UV-vis absorption spectroscopy. Fe3+ ions in a-Fe2O3 nanocrystal structure are substituted by Cu2+ ions. This leads to lattice distortion and increase in hole trapping sites.2 XRD pattern shows that crystal structure remains as almost same when adjusting the amount of Cu2+ ions. Due to charge imbalance and crystal distortion, when Cu2+ ions occupied Fe3+ sites, hole trapping occurred leading to the decrease in PEC value. Furthermore, electrochemical impedance value was increased as Cu doping increased, which was consistent with PEC data. Also, incident photon to electron conversion efficiency has decreased by doping.