Coupling of BiOCl Ultrathin Nanosheets with Carbon Quantum Dots for Enhanced Photocatalytic Performance

Abstract

Abstract Over the past few decades, photocatalysis technology has received extensive attention because of its potential to mitigate or solve energy and environmental pollution problems.Designing novel materials with outstanding photocatalytic activities has become a research hotspot in this field. In this study, we prepared a series of photocatalysts in which BiOCl nanosheets were modified with carbon quantum dots (CQDs) to form CQDs/BiOCl composites by using a simple solvothermal method. The photocatalytic performance of the resulting CQDs/BiOCl composite photocatalysts was assessed by rhodamine B and tetracycline degradation under visible-light irradiation. Compared with bare BiOCl, the photocatalytic activity of the CQDs/BiOCl composites was significantly enhanced, and the 5 wt% CQDs/BiOCl composite exhibited the highest photocatalytic activity with a degradation efficiency of 94.5% after 30 min of irradiation. Moreover, photocatalytic N 2 reduction performance was significantly improved after introducing CQDs. The 5 wt% CQDs/BiOCl composite displayed the highest photocatalytic N 2 reduction performance to yield NH 3 (346.25 μmol/(g h)), which is significantly higher than those of 3 wt% CQDs/BiOCl (256.04 μmol/(g h)), 7 wt% CQDs/BiOCl (254.07 μmol/(g h)), and bare BiOCl (240.19 μmol/(g h)). Our systematic characterizations revealed that the key role of CQDs in improving photocatalytic performance is due to their increased light harvesting capacity, remarkable electron transfer ability, and higher photocatalytic activity sites. Graphical Abstract This work reports a novel CQDs/BiOCl composite photocatalyst for efficiently removing contaminants from water.