Textile dyes removing from the wastewater by green synthesized Cu-doped ZnO photocatalysts under the simulated sunlight illumination.

Herein, Cu-doped ZnO photocatalysts were prepared via green synthesis method with utilization of Cannabis Sativa leaves. The catalytic activity was evaluated through the degradation of methylene blue (MB) and rhodamine B (RhB) under the simulated sunlight illumination. XRD, FESEM, EDAX, FTIR, BET-BJH and DRS were used for characterizations of Cu-doped ZnO. The results showed that, 3 wt % Cu-doped ZnO (CuZn3) displayed the excellent characterizations such as uniform dispersion, lower energy bandgap, smaller average particle size and greater surface area. For the photocatalysts with higher Cu loading (more than 3 wt %), non-uniform dispersion with larger particles, lower specific surface area and higher energy bandgap were found. The average particle size and energy bandgap for CuZn3 were 37.7 nm and 2.9 eV, respectively. Due to the superior properties, CuZn3 presented the highest amount of dyes degradations. After 180 min test, MB and RhB degradations by CuZn3 were 92.1 and 94.2 %, respectively. Moreover, it was found that optimum amount of CuZn3 was 100 ppm. Furthermore, applying of various scavengers revealed that hydroxyl radicals, superoxide radicals, and photo-generated electrons were the primary forms of radicals involved in dyes degradation using Cu-doped ZnO photocatalysts. [ABSTRACT FROM AUTHOR]