Assembly of direct Z-scheme ZnIn2S4/BiVO4 composite for enhanced photodegradation of tetracycline hydrochloride

The development of innovative, low-cost, and effective photocatalysts for the degradation of organic pollutants is critical for wastewater treatment. Herein, a novel spindle-shaped BiVO4 was prepared to construct direct ZnIn2S4/BiVO(4 )Z-scheme heterojunction photocatalysts for the first time. The compositions, microscopic structure, optical and electrochemical properties of nanocomposites were studied. Moreover, the degradation performance to tetracycline hydrochloride was tested to evaluate the photocatalytic property of prepared samples. The results revealed that the degradation rate of the optimal sample reached 93.3% after 2 h of light exposure, which is 2 and 2.5 times higher than that of pure ZnIn2S4 and BiVO4, respectively. The higher photocatalytic activity was ascribed to the increased charge carrier separation and migration efficiency provided by the unique Z-scheme structure of the ZnIn2S4/BiVO4. The quenching experiments indicated that h(+) and center dot O-2(-) served as the main active species in the process of photocatalytic degradation. Hence, the excellent catalytic activity of ZnIn2S4/BiVO4 provides a new method for the elimination of organic pollutants in the environment.