文献类型：期刊文献

英文题名：Effect of Lateral Size of Graphene Quantum Dots on Their Properties and Application

作者：Zhang, Fangwei[1];Liu, Fei[2];Wang, Chong[2];Xin, Xiaozhen[2];Liu, Jingyuan[2];Guo, Shouwu[1];Zhang, Jingyan[2]

机构：[1]Shanghai Jiao Tong Univ, Sch Elect Informat & Elect Engn, Dept Elect Engn, Shanghai 200240, Peoples R China;[2]E China Univ Sci & Technol, Shanghai Key Lab New Drug Design, Sch Pharm, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2016

卷号：8

期号：3

起止页码：2104

外文期刊名：ACS APPLIED MATERIALS & INTERFACES

收录：;EI(收录号：20160501875651);WOS:【SCI-EXPANDED(收录号:WOS:000369044100067)】；

基金：This research was carried out with financial support from the national "973 Program" of China (Nos. 2014CB260411 and 2015CB931801), National Science Foundation of China (Nos. 11374205, 21376148), the State Key Laboratory of Bioreactor Engineering (No. 2060204), 111 Project (No. B07023), the Shanghai Committee of Science and Technology (No. 11DZ2260600), and national "863" Program of China (No. 2012AA022603).

语种：英文

外文关键词：graphene quantum dot; gel electrophoresis; lateral size; photoluminescence

摘要：Well-defined graphene quantum dots (GQDs) are crucial for their biological applications and the construction of nanoscaled optoelectronic and electronic devices. However, as-synthesized GQDs reported in many works assume a very wide lateral size distribution; thus, their apparent properties cannot truthfully reflect intrinsic properties of the well-defined GQDs, and more importantly, the applications of GQDs will be affected and limited as well. In this work, we demonstrated that different sized GQDs with a narrow size distribution could be obtained via gel electrophoresis of the crude GQDs prepared through a photo-Fenton reaction of graphene oxide (GO). It is illustrated that the photoluminesce (PL) emissions of the well-defined GQDs originated mainly from the peripheral carboxylic groups and conjugated carbon backbone planes through fluorescence and UV vis spectroscopies. More importantly, our findings challenge the notion that the excitation wavelength dependent PL property of the as-synthesized GQDs is the intrinsic property of the size-defined GQDs. Preliminary data at the cellular level indicated that the small sized GQDs exhibit weaker quenching DNA dye ability but higher toxicity to the cells compared to that of the as-synthesized GQDs. This discovery is essential to explore applications of the GQDs in pharmaceutics and to understand the origin of the optoelectronic properties of GQDs.