介孔氧化镁中碳量子点三重态的产生及其磷光和光催化特性  

Generating triplet states in carbon quantum dots confined in mesoporous MgO for phosphorescence and photocatalysis applications

作　　者：姚清 吴浩怡 梁锦基 王传龙 金亚洪 胡义华 唐友宏 Qing Yao;Haoyi Wu;Jinji Liang;Chuanlong Wang;Yahong Jin;Yihua Hu;Youhong Tang(School of Physics and Optoelectronic Engineering,Guangdong University of Technology,Guangzhou 510006,China;Institute for NanoScale Science and Technology,College of Science and Engineering,Flinders University,South Australia 5042,Australia)

机构地区：[1]School of Physics and Optoelectronic Engineering,Guangdong University of Technology,Guangzhou 510006,China [2]Institute for NanoScale Science and Technology,College of Science and Engineering,Flinders University,South Australia 5042,Australia

出　　处：《Science China Materials》2024年第1期170-178,共9页中国科学（材料科学）（英文版）

基　　金：supported by the National Natural Science Foundation of China (51972065);Guangdong Natural Science Foundation (2021A1515010179)。

摘　　要：本文通过高温热解柠檬酸(CA)和Mg_(2)(OH)_(2)CO_(3)的混合物将碳量子点嵌入到介孔MgO中,并观察到室温磷光.碳量子点通过含氧官能团与MgO连接并被限制于MgO介孔中.由于碳量子点表面原子自动受限,其电子自旋角动量将改变,产生自旋三重态并可获得磷光.碳量子点与MgO的杂化复合物表现出典型的激发依赖现象,当激发波长增加时,荧光和室温磷光产生明显的红移,因此具有良好的防伪应用价值.CA在MgO中热解,使碳量子点与MgO的杂化复合物具有较高的比表面积和较宽的吸收波长.碳量子点的三重态电子延迟复合提高了载流子分离效率.因此与对照组样品对比,该复合物对有机污染物的光催化降解能力有显著提高.In this study,room-temperature phosphores-cence(RTP)was observed from carbon quantum dots(CQDs),which were embedded in porous magnesium oxide(MgO)via the high-temperature pyrolysis of citric acid(CA)and Mg_(2)(OH)_(2)CO_(3).The mesoporous MgO confined the CQDs via oxygen-containing groups and through changes in the angular momentum of surface atoms.Then,triplet states were created and the MgO-CQDs hybridization showed a typical excitation-dependent phenomenon,wherein fluorescence and RTP were red shifted when the excitation wavelength shifted to a longer wavelength,rendering an anticounterfeiting application.Moreover,the pyrolysis of CA in MgO resulted in a high specific surface area and extended the absorption wavelength range.Accompanied with the enhanced charge separation induced by delayed recombination of electrons and holes in the surface triplet state of CQDs,hybridization revealed an improved photocatalytic capability to degrade organic pollu-tants compared with pure MgO and its hybridization of CQDs without the Mg2(OH)2CO3 precursor.

关 键 词：自旋角动量 室温磷光 激发波长 载流子分离 三重态 碳量子点 含氧官能团 高温热解 

分 类 号：X505[环境科学与工程—环境工程] O643.36[理学—物理化学] O644.1[理学—化学]