Hollow mesoporous g-C3N4/Ag2CrO4 photocatalysis with direct Z-scheme: Excellent degradation performance for antibiotics and dyes

The hollow mesoporous g-C3N4/Ag2CrO4 (HCN/ACO-x (x = 0.5, 1, 2, 4, 6)) photocatalysts with outstanding degradation activity for antibiotics and dyes under visible light irradiation were prepared in this study. XRD, XPS, FESEM, HRTEM, N-2 adsorption-desorption, and UV-vis DRS were used to characterize the phase structure, morphology, and optical properties of the prepared samples. The HCN/ACO-x (x = 0.5, 1, 2, 4, 6) composites had enhanced photocatalytic activity for photodegradation of colorless antibiotics tetracycline hydrochloride (TC) and rhodamine (RhB) than those of g-C3N4 (CN), hollow mesoporous g-C3N4 (HCN), and Ag2CrO4 (ACO) samples, with HCN/ACO-4 sample showing the highest photocatalytic performance. The hollow mesoporous structure is expected to trap more incident photons in the HCN microspheres, further improving visible light absorption. Moreover, by building the internal electric field and forming of band bending in the interface between HCN and ACO, a direct Z-scheme HCN/ACO photocatalysis was produced, which exhibited superior separation of photogenerated holes and electrons, further leading to excellent photocatalytic performance for degradation of antibiotics and dyes.