Guo Tingxuan, Yang Fulin, Liu Can, Hou Defa, Zheng Yunwu, Gao Hui, Lin Xu, Sun Hao
National Joint Engineering Research Center for Highly-Efficient Utilization Technology of Forestry Resources, Southwest Forestry University, 300 Bailong Road, Kunming 650224, Yunnan Province, China.
Yunnan University of Chinese Medicine, 1076, Yuhua Road, University City of Chenggong, 650500 Kunming, Yunnan Province, China.
Inorg Chem. 2024 Jun 17;63(24):11478-11486. doi: 10.1021/acs.inorgchem.4c01692. Epub 2024 May 31.
In the preparation of carbon dots (CDs), precursors are crucial, and abundant precursors endow CDs with various structures and fluorescence characteristics. Furan (FU) and its derivatives are considered excellent carbonization materials due to their π conjugated structures and active functional groups, such as hydroxyl and aldehyde groups. Herein, we prepare FU-derivative-based CDs by a solvothermal method and investigate the influences of the precursor structure on the fluorescence characteristics. Surprisingly, CDs prepared from 5-hydroxymethylfurfural (HMF) with both aldehyde and hydroxyl groups exhibit red-shifted fluorescence characteristics in the solid state. We postulate that this solid-state fluorescence characteristic is due to the enhancement of supramolecular cross-linking fluorescence between CDs. The unique precursor structure leads to carboxyl groups on the surface of HMF-CDs that are conducive to the hydrogen bond formation. As the concentration of CDs increases, the hydrogen bonding effect increases, leading to a red-shift in the fluorescence wavelength. Therefore, basically full-color CDs/poly(vinyl alcohol) (PVA) phosphor-based light-emitting diodes can be achieved by controlling the degree of supramolecular cross-linking of CDs in PVA. This research provides a new approach for the preparation of solid-state luminescent CDs.
在碳点（CDs）的制备过程中，前驱体至关重要，丰富的前驱体赋予碳点各种结构和荧光特性。呋喃（FU）及其衍生物因其π共轭结构以及羟基和醛基等活性官能团而被视为优良的碳化材料。在此，我们通过溶剂热法制备了基于FU衍生物的碳点，并研究了前驱体结构对荧光特性的影响。令人惊讶的是，由同时含有醛基和羟基的5-羟甲基糠醛（HMF）制备的碳点在固态下呈现出红移荧光特性。我们推测这种固态荧光特性是由于碳点之间超分子交联荧光的增强。独特的前驱体结构导致HMF-CDs表面形成羧基，有利于氢键的形成。随着碳点浓度的增加，氢键效应增强，导致荧光波长红移。因此，通过控制碳点在聚乙烯醇（PVA）中的超分子交联程度，基本上可以实现全色的碳点/聚乙烯醇（PVA）磷光体发光二极管。这项研究为固态发光碳点的制备提供了一种新方法。
