Green-emitting carbon quantum dots as a dual-mode fluorescent and colorimetric sensor for hypochlorite

In this work, green-emitting carbon quantum dots were successfully prepared through a facile one-step solid-state reaction method. The obtained green-emitting carbon dots (G-CDs) showed good fluorescence stability in NaCl aqueous solution and different pH values. Moreover, the G-CDs showed high sensitivity and selectivity for detecting hypochlorite by both fluorometry and colorimetry. Under the optimized condition, a highly sensitive detection of hypochlorite was established in the range of 0.2-100 mu M and 10-150 mu M for fluorescent and colorimetric methods, respectively. The corresponding limits of detection (LOD) were 0.0781 mu M and 1.82 mu M, respectively. Therefore, the G-CDs were successfully applied to determinate hypochlorite in actual water samples. In addition, a paper-based sensor loading with the G-CDs was also developed for rapid visual detection of hypochlorite. The results suggested that the G-CDs could be a promising candidate to detect hypochlorite.

Automated summary

Green-emitting carbon quantum dots were prepared successfully with a simple method, showing good fluorescence stability in aqueous solution. These carbon quantum dots exhibited high sensitivity and selectivity for detecting hypochlorite, and were successfully applied in determining hypochlorite in actual water samples.