Fluorescence Properties of ZnOQDs-GO-g-C(3)N(4) Nanocomposites

In this paper, the fluorescence properties of ZnOQD-GO-g-C(3)N(4) composite materials (ZCGQDs) were studied. Firstly, the addition of a silane coupling agent (APTES) in the synthesis process was explored, and it was found that the addition of 0.04 g·mL(−1) APTES had the largest relative fluorescence intensity and the highest quenching efficiency. The selectivity of ZCGQDs for metal ions was also investigated, and it was found that ZCGQDs showed good selectivity for Cu(2+). ZCGQDs were optimally mixed with Cu(2+) for 15 min. ZCGQDs also had good anti-interference capability toward Cu(2+). There was a linear relationship between the concentration of Cu(2+) and the fluorescence intensity of ZCGQDs in the range of 1~100 µM. The regression equation was found to be F(0)/F = 0.9687 + 0.12343C. The detection limit of Cu(2+) was about 1.74 μM. The quenching mechanism was also analyzed.