The Enhanced Photocatalytic Performance of Pr Doped Cu2O Under Visible Light

Abstract Cuprous oxide (Cu 2 O) has a narrow band gap of 2.1–2.3 eV, which facilitates the absorption of visible light and the photocatalytic removal of pollutants from water. However, the catalytic efficiency of Cu 2 O has been affected by the rapidly compounding carriers in the photocatalytic process. In order to achieve adequate separation of the photogenerated carriers, a straightforward liquid‐phase reduction technique was used in this study to successfully obtain praseodymium‐doped cuprous oxide Pr : Cu 2 O (0, 1, 3, and 5 mol %). Praseodymium ions were successfully doped into the Cu 2 O lattice interstitial, as demonstrated by XRD and SEM studies, and the doped praseodymium ions decreased the crystallite size. The FT‐IR peak also confirmed the existence of Cu 2 O at 631 cm −1 . With the increase of Pr doping to 3 %, the band gap gradually decreased to 2.12 eV. Experiments on the degradation of methyl orange (MO) under visible light irradiation showed that 3 % Pr : Cu 2 O photocatalyst showed the best photocatalytic performance. The Pr doping reduced the recombination of photogenerated electron‐hole pairs and enhanced the photocatalytic activity of Cu 2 O, according to the analysis results of PL, EIS and transient photocurrent response. Combining these results with active radical capture experiments, the functioning mechanism of the Pr : Cu 2 O photocatalyst was examined.