CQDs modified PbBiO2Cl nanosheets with improved molecular oxygen activation ability for photodegradation of organic contaminants

Novel carbon quantum dots (CQDs) modified PbBiO2Cl nanosheets, 0D/2D hybird photocatalyst has been firstly prepared via the reactive ionic liquid 1-hexadecyl-3 methylimidazolium chlorine assisted facile solvothermal approach. PbBiO2Cl nanosheets were designed to shorten the migration distance from bulk phase to the surface for the charge carriers, while CQDs was introduced to accelerate the transfer of surface charge carriers as well as activate molecular oxygen. Various techniques were conducted to explore structures, morphologies, optical and electrochemical properties of the as-prepared materials. Furthermore, the photocatalytic performance of CQDs/PbBiO2Cl materials were appraised via the photodegradation of antibiotic agent ciprofioxacin (CIP), tetracycline (TC) and endocrine disrupter bisphenol A (BPA) under visible light irradiation. The results demonstrated that the photocatalytic activities of CQDs modified PbBiO2Cl materials has a significantly enhancement compared to pure PbBiO2Cl nanosheets and the 3 wt% CQDs/PbBiO2Cl material displays the highest performance. In addition, electron spin resonance (ESR) experiments and radicals quenching experiments were employed to prove that the superoxide radicals and holes were the main active species during the photocatalytic process. Based on the above results, a possible photocatalytic mechanism was put forward. This research aims to develop more hybrid photocatalysts and hope to make progress in environmental remediation.