摘要
提出了一种通过硼(B)元素掺杂调控无基质复合的“纯”碳点(CDs)陷阱密度与能级和延长其余辉持续时间的方法.研究结果表明,在以1,4-苯二硼酸、氢氧化钠和三聚氰胺为原料制备的3种CDs中,硼元素以B—N和B—C键的形式掺入到CDs的结构中,且掺杂浓度随硼源(1,4-苯二硼酸)比例的增加而升高.这既增加了CDs的陷阱密度,也扩大了陷阱能级与激发三重态之间的能级差异.此外,C=O和C=N键合的含量也随之增加,促进了三重态激子的生成和系间窜跃.利用陷阱捕获和存储三重态激子,并使其缓慢释放,可显著延长三重态激子的弛豫时间,使CDs的余辉寿命从0.764 s延长至1.224 s,余辉持续时间延长了4倍.最后,基于3种CDs余辉寿命的差异,设计了一种基于CDs余辉强度随时间动态衰减的信息存储和加密方法.
A method for regulating the trap levels of matrix-free carbon dots(CDs)through boron(B)doping is demonstrated,significantly prolonging their afterglow duration.Further studies reveal that B is incorporated into the CDs in the forms of B—N and B—C bonds when the CDs are synthesized from 1,4-phenylenediboronic acid,sodium hydroxide,and melamine.The B content increases with the proportion of the B source(i.e.,1,4-phenylenediboronic acid).This process not only enhances the trap density in the CDs but also increases the energy level difference between the trap energy level and the excited triplet state.Moreover,the elevated levels of C=O and C=N bonds facilitate the generation of triplet excitons and intersystem crossing.As traps capture and store triplet excitons for gradual release,the afterglow lifetime of CDs is extended from 0.764 s to 1.224 s,effectively quadrupling the afterglow duration.Finally,based on variations in their afterglow durations,potential applications for information storage and encryption using these CDs are demonstrated.
作者
李逢时
蒋凯
童鑫园
武永健
林恒伟
LI Fengshi;JIANG Kai;TONG Xinyuan;WU Yongjian;LIN Hengwei(International Joint Research Center for Photo-responsive Molecules and Materials,School of Chemical and Material Engineering,Jiangnan University,Wuxi 214122,China)
出处
《高等学校化学学报》
北大核心
2025年第6期192-200,共9页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:52372047)资助.
关键词
碳点
室温余辉
陷阱
元素掺杂
动态信息加密
Carbon dots
Room temperature afterglow
Traps
Element doping
Dynamic information encryption
