长余辉碳点材料研究进展

Research progress of long afterglow carbon dots materials

长余辉材料因其特殊的发光效果而广受关注,但现有长余辉体系普遍存在成本高、工艺烦琐等问题,因此构筑廉价高效的新型余辉材料体系成为主流趋势.碳点是近年来发展迅速的荧光纳米碳材料之一,除其荧光特性广受重视之外,以室温磷光(RTP)、热活化延迟荧光(TADF)为主的余辉特性也引起广大科研工作者的关注.综合碳点低成本、低毒且制备手段简便一系列优点来看,长余辉碳点及其复合材料有望成为下一代余辉材料的主力军之一.本文整理了近年来长余辉碳点的相关工作,首先概述碳点及其主要长余辉特性,接着介绍了长余辉碳点材料的主流制备手段,就化学结构对碳点长余辉特性影响进行讨论后,对长余辉碳点在防伪、信息加密以及传感领域的应用进行介绍,最后根据当前各项工作成果,对长余辉碳点材料的未来发展做出展望和建议.

Long afterglow materials,which can still emit light for a period of time after stopping external excitation,are one of the earliest luminescent materials that have been understood and applied by people.Because of their special luminous effects,they have attracted wide attention and are widely used in fluorescent lighting,information security and encryption.Existing long afterglow materials are generally alkali metal material systems doped with sulfides and rare earths.Based on their common problems such as high cost,high biological toxicity,and cumbersome processes,the construction of a new type of afterglow material system with low-cost and high efficiency has become the mainstream trend.In recent years,carbon dots are one of the fluorescent nano-carbon materials that have developed rapidly.In recent years,compared with fluorescence characteristics that have been widely valued,the afterglow characteristics of room temperature phosphorescence(RTP)and thermally activated delayed fluorescence(TADF)have also attracted the attention of the majority of scientific researchers.However,limited by their own chemical structure,the afterglow characteristics of carbon dots materials are often not ideal at room temperature,which may limit their further application.At present,some researchers have successfully prepared a variety of carbon dots and their composite materials with stable afterglow characteristics at room temperature by selecting suitable reaction systems,using heteroatom doping,rigid matrix composite and other modification methods,and applied them to anti-counterfeiting,encryption and many other fields.Even so,there are still many unsolved problems,such as short afterglow lifetime,low quantum yield,single afterglow emission color,limited wavelength range,etc.,which require further research.In general,considering the advantages of low-cost,low-toxicity and simple preparation methods of carbon dots,long afterglow carbon dots and their composite materials are still expected to become one of the main forces of the next generation of afterglow materials.This article summarizes the related work of long afterglow carbon dots in recent years.First,it briefly summarizes the carbon dots and the main long afterglow characteristics of them.Then introduces the mainstream preparation methods of long afterglow carbon dots.After the part of the influence of the afterglow characteristics,the applications of long afterglow carbon dots in the fields of anti-counterfeiting,information encryption and fluorescent sensing were introduced.Finally,based on the current work results,the future development of long afterglow carbon dots and their composite materials was prospected.