Enhanced visible-light photocatalytic activity of ZrO2/gCN composite by introducing nitrogen vacancies with H2 plasma treatment

The abuse of tetracycline antibiotics (TCs) has caused serious environmental pollution problems in recent years due to excessive use of biomedicine, healthcare, animal husbandry and other fields. How to effectively remove TCs contaminants from water has been one of research emphasis on environment protection. In this work, we have successfully prepared a composite photocatalyst (P16-ZrO2/gCN) by physical mixing method and H2 plasma treatment at room temperature. The ZrO2 nanoparticles and H2 plasma treatment have synergetic effects on photocatalytic performance of gCN for degradation of TCs, and the highest degradation rate is achieved with 16 mins plasma treatment. According to BET, XPS and EPR results, more mesopores and nitrogen vacancies (NVs) are introduced by H2 plasma treatment. Furthermore, In-situ TRPL spectra illustrate that ZrO2 nanoparticles and H2 plasma treatment facilitate charge transfer process of catalysts. Overall, this work firstly reports utilizing ZrO2 nanoparticles/H2 plasma treatment together to boost photocatalytic performance of gCN and provides a low-cost approach for preparation of other photocatalysts.