A Z-scheme iron-based hollow microsphere with enhanced photocatalytic performance for tetracycline degradation

Photocatalytic oxidation has been considered as a potential method for elimination of organic contaminants with low energy consumption. Photodegradation performance is subject to some factors: bandgap, band-edge positions and carrier separation efficiency. Z-scheme heterojunction system can improve photocatalytic performance through optimizing these factors. Thus, a Z-scheme α-Fe2O3/g-C3N4 hollow microsphere was obtained via controlled crosslinking and hydrolysis process (uniform dispersion of two components: through crosslinking; hollow structure: from self-sacrifice of glucose). Numerous constructed pores are beneficial for tetracycline (TC) to adsorb on photocatalysts (7.9 mg/L), which further accelerates TC degradation process. TC degradation rate increased to 67% over α-Fe2O3/g-C3N4-4 (g-C3N4: 48%, α-Fe2O3: 44%) after 2 h irradiation, which results from the quick capture and separation of photogenerated electron–hole pairs and the oxidation and reduction abilities of photocatalysts. This work presents an insight into promoting degradation efficiency of antibiotics and simultaneously reducing photocatalyst cost.