To deal with heavy metal pollution, a novel fluorescent chitosan-based hydrogel incorporating titanate and cellulose nanofibers modified with carbon dots was prepared to effectively detect and remove Cr(VI). The composition and structure of this chitosan-based hydrogel were analyzed. The performance of the fluorescent chitosan-based hydrogel in Cr(VI) adsorption was evaluated through a contrast experiment with the normal chitosan hydrogel without carbon dots. The results showed that the fluorescent chitosan-based hydrogel had a higher adsorption ability of Cr(VI) (maximum adsorption capacity, 228.2 mg g⁻¹). The effect of the initial concentration of Cr(VI) and the contact time were also evaluated. The results confirmed that the adsorption isotherm was according to the Langmuir model, and the adsorption kinetics followed the pseudo-second-order model. Furthermore, as a fluorescent sensor for Cr(VI), the detection sensitivity and selectivity were examined. The quantitative detection of Cr(VI) was achieved in the linear range of 10–80 mg L⁻¹. Furthermore, for this fluorescent chitosan-based hydrogel, the mechanism for highly efficient adsorption and detection of Cr(VI) was analyzed via FTIR and XPS. These results showed that the excellent sorption and sensing abilities of Cr(VI) may be mainly attributed to the porous structures and the additional titanate and cellulose nanofibers modified with carbon dots improving sorption ability of Cr(VI) and providing a rapid visual response to Cr(VI).

为了处理重金属污染，制备了一种新型的结合壳聚糖和碳纳米管修饰的纤维素纳米纤维的荧光壳聚糖荧光水凝胶，可有效检测和去除六价铬。分析了这种基于壳聚糖的水凝胶的组成和结构。荧光壳聚糖基水凝胶在Cr（VI）吸附中的性能是通过与不含碳点的普通壳聚糖水凝胶进行对比实验来评估的。结果表明，基于壳聚糖的荧光水凝胶具有较高的Cr（VI）吸附能力（最大吸附能力为228.2 mg g ^-1）。还评估了Cr（VI）初始浓度和接触时间的影响。结果证实，吸附等温线符合Langmuir模型，吸附动力学符合拟二级模型。此外，作为Cr（VI）的荧光传感器，检查了检测灵敏度和选择性。Cr（VI）的定量检测在10–80 mg L ^-1的线性范围内完成。此外，对于这种基于壳聚糖的荧光水凝胶，通过FTIR和XPS分析了高效吸附和检测Cr（VI）的机理。这些结果表明，Cr（VI）的优异吸附和感测能力可能主要归因于多孔结构以及碳点修饰的其他钛酸酯和纤维素纳米纤维可提高Cr（VI）的吸附能力并提供对Cr的快速视觉响应（VI）。