Study on multifunctional nitrogen and boron co-doped carbon quantum dots for detecting metal ions and improving the photocatalytic performance of BiOCl.

Herein, we have successfully prepared multifunctional nitrogen–boron co-doped carbon quantum dots (N,B-CQDs) with excellent performance by a one-step hydrothermal method and further applied them to the design of highly efficient fluorescent probes and visible light responsive photocatalysts. N,B-CQDs have excellent selectivity and high sensitivity to Fe3+ and Hg2+, with LODs of 1.8 μM and 0.34 μM, respectively. The experimental results show that the fluorescence quenching mechanism of Fe3+ and Hg2+ detected by N,S-CQDs is the result of dynamic quenching and static quenching. Besides, BiOCl modified by N,S-CQDs(BiOCl/N,B-CQDs) was prepared by one-step hydrothermal method, and the morphology of catalysts and the adhesion of N,B-CQDs were observed by several scientific methods. The photocatalytic results showed that the degradation rate of RhB by BiOCl/N,B-CQDs was up to 99.4% under optimal conditions, which was higher than that of BiOCl (80%). Free radical quenching experiments proved that ·OH and ·O2− were the main active substances in the reaction process. Finally, the aim of this study is to offer a novel approach to developing multi-function CQDs as a sensor for metal ions and their modified composites as visible light-induced photocatalysts for the effective detection and degradation of contaminants. [ABSTRACT FROM AUTHOR]