Formation and fluorescent mechanism of red emissive carbon dots from o-phenylenediamine and catechol system  

作　　者：Pengfei Li Shanshan Xue Lu Sun Xupeng Zong Li An Dan Quo Xiayan Wang Zaicheng Sun 

机构地区：[1]Center of Excellence for Environmental Safety and Biological Effects,Bejing Key Laboratory for Green Catalysis and Separation,Department of Chemistry,Beijing Universityof Technology,100124 Bejing,China

出　　处：《Light(Science & Applications)》2022年第11期2687-2697,共11页光（科学与应用)（英文版）

基　　金：This study was financially supported by the Bejing Municipal High-Level Innovative Team Building Program(grant no.IDHT20180504);the Bejing Outstanding Young Scientists Program(BJWZYJH01201910005017);the National Natural Science Foundation of China(grantnos.22272003,21872001,51801006,and 21805004);the Key Project of the National Natural Science Foundation of China(21936001 and 21801092);the Beijing Natural Science Foundation(grant no.2192005);the Beijing Municipal Science and Natural Science Fund Project(grant no.KM201910005016).

摘　　要：Carbon dots(CDs)as the advancing fluorescent carbon nanomaterial have superior potential and prospective.However,the ambiguous photoluminescence(PL)mechanism and intricate structure-function relationship become the greatest hindrances in the development and applications of CDs.Herein,red emissive CDs were synthesized in high yield from O-phenylenediamine(oPD)and catechol(CAT).The PL mechanism of the CDs is considered as the molecular state fluorophores because 5,14-dihydroquinoxalino[2,3-b]phenazine(DHQP)is separated and exhibits the same PL properties and behavior as the CDs.These include the peak position and shape of the PL emission and PL excitation and the emission dependence on pH and solvent polarity.Both of them display close PL lifetime decays.Based on these,we deduce that DHQP is the fluorophore of the red emissive CDs and the PL mechanism of CDs is similar to DHQP.During the PL emission of CDs,the electron of the molecule state can transfer to CDs.The formation process of DHQP is further confirmed by the reaction intermediates(phthalazine,dimers)and oPD.These findings provide insights into the PL mechanism of this type of CDs and may guide the further development of tunable CDs for tailored properties.

关 键 词：properties MECHANISM CATECHOL 

分 类 号：O64[理学—物理化学]