College of Science, Central South University of Forestry and Technology, Changsha 410004, China.
College of Science, Central South University of Forestry and Technology, Changsha 410004, China; College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China.
Sci Total Environ. 2021 Mar 15;760:143395. doi: 10.1016/j.scitotenv.2020.143395. Epub 2020 Nov 5.
A novel fluorescent lignin-based hydrogel with cellulose nanofibers and carbon dots (CDs) was synthesized for the high-value utilization of lignin and control of hexavalent chromium (Cr(VI)). Its chemical and physical structure was characterized, and its Cr(VI) sorption performance was evaluated. The results demonstrated that 3D porous structures were constructed in this hydrogel. The maximum adsorption capacity of this hydrogel was 599.9 mg/g, and its sorption performance met Freundlich and pseudo-second-order models. Meanwhile, this novel hydrogel exhibited high sensitivity to Cr(VI), with a limit of detection of 11.2 mg/L and a wide linear range from 15 to 200 mg/L. Moreover, its mechanism for efficiently adsorbing and detecting Cr(VI) was analyzed. The results confirmed that the efficient adsorption and detection were due to these 3D porous structures generated by the lignin and cellulose nanofibers modified with CDs. The porous structures provided many active sites and ion transport channels, thereby improving the adsorption, and stabilized the fluorescence signal, thus enhancing the detection.
一种新型的基于荧光木质素的水凝胶，其中含有纤维素纳米纤维和碳点（CDs），被合成用于木质素的高价值利用和六价铬（Cr(VI)）的控制。对其化学和物理结构进行了表征，并评估了其对 Cr(VI)的吸附性能。结果表明，在这种水凝胶中构建了 3D 多孔结构。该水凝胶的最大吸附容量为 599.9 mg/g，其吸附性能符合 Freundlich 和拟二级模型。同时，这种新型水凝胶对 Cr(VI)表现出高灵敏度，检测限为 11.2 mg/L，线性范围从 15 到 200 mg/L 很宽。此外，还分析了其高效吸附和检测 Cr(VI)的机制。结果证实，高效吸附和检测是由于木质素和经 CDs 改性的纤维素纳米纤维生成的 3D 多孔结构所致。这些多孔结构提供了许多活性位点和离子传输通道，从而提高了吸附，并稳定了荧光信号，从而增强了检测。
