碱木质素碳点的制备及对Fe3+检测性能研究

Preparation of Alkali Lignin Carbon Dots and Study on Fe3+ Detection Performance

关键词:  碱木质素  乙二胺  碳点  荧光猝灭  Fe³⁺离子检测

Key Words:alkali lignin  ethylenediamine  carbon dots  fluorescence quenching  Fe³⁺ ion detection

摘要:以碱木质素（Alkali lignin，AL）为碳源、乙二胺（Ethanediamine，EDA）为钝化剂、双氧水（H₂O₂）为氧化剂，利用简单、绿色、高效的水热法制备碱木质素碳点（ALE-CDs）。以荧光性能为指标，通过单因素实验优选出ALE-CDs的最佳制备工艺。结果表明，ALE-CDs表面存在大量的羟基（—OH）、羧基（—COOH）和氨基（—NH₂）等官能团，在水中具有优良的分散性和稳定性，荧光量子产率及寿命分别为19.20%和6.03 ns。利用ALE-CDs为荧光探针检测不同金属离子，发现ALE-CDs对Fe³⁺表现出较好的选择性，荧光强度与Fe³⁺浓度（0~50 μmol/L）呈良好的线性关系，Fe³⁺检出限约为1.66 μmol/L。

Abstract:Lignin-based carbon dots （ALE-CDs） were synthesized via a simple， green and efficient hydrothermal method， using alkali lignin （AL） as carbon source， ethylenediamine （EDA） as passivator and hydrogen peroxide （H₂O₂） as oxidant. The optimal preparation process of ALE-CDs was optimized by single factor experiment using fluorescence performance as the index. It was found that the ALE-CDs were rich in functional groups on surface， such as hydroxyl （—OH）， carboxyl （—COOH） and amino （—NH₂）， and showed excellent dispersion and stability in water. The fluorescence quantum yield and lifetime were 19.20% and 6.03 ns， respectively. Using ALE-CDs as fluorescent probes to detect different metal ions， it was found that ALE-CDs showed good selectivity for Fe³⁺， and the fluorescence intensity had a good linear relationship with the Fe³⁺ concentration （0~50 μmol/L）， and the detection limit of Fe³⁺ could reach 1.66 μmol/L.