Mint powder assisted synthesis of CQDs/BiOCl with tunable OVs and improved photocatalytic property

Abstract

Development of advanced technologies for the removal of perfluorooctanoic acid (PFOA) from waterbody has been a challenge because of the persistent, widely distributed and potentially toxic nature of PFOA in the aquatic environment as well as the high binding energy of C-F bond, therefore, it is difficult to remove PFOA by routine heating, ultraviolet radiation and biological degradation. In this study, BiOCl-based photocatalysts containing carbon quantum dots (CQDs) with visible light reactivity were prepared by a hydrothermal approach using mint powder (MNP) as raw material for CQDs. The prepared samples exhibit self-assembled three dimensions(3D) flower-like microspheres with adjustable oxygen vacancies (OVs). The experimental results show that the activity of BiOCl modified with CQDs is significantly increased compared to that of the reference BiOCl. When the mass ratio of MNP/BiOCl is 2%, the 2% CQDs/BiOCl photocatalyst shows a three-fold enhancement in degradation activity toward destruction of rhodamine (RhB) compared with the reference BiOCl under visible light irradiation. Additionally, degradation activity of 2% CQDs/BiOCl catalyst toward decontamination of PFOA under UV light irradiation also increases. This presentation offers a robust strategy for the synthesis of significantly efficient photocatalysts for detoxification of the organic pollutants.