石墨烯
量子点
材料科学
氢氧化物
剥脱关节
氧化物
碱金属
拉曼光谱
电解质
无机化学
化学
纳米技术
电极
物理化学
物理
光学
有机化学
冶金
作者
Satyaprakash Ahirwar,Sudhanshu Mallick,D. Bahadur
出处
期刊:ACS omega
[American Chemical Society]
日期:2017-11-28
卷期号:2 (11): 8343-8353
被引量:251
标识
DOI:10.1021/acsomega.7b01539
摘要
In this study, we present the preparation of graphene quantum dots (GQDs) and graphene oxide quantum dots (GOQDs). GQDs/GOQDs are prepared by an easy electrochemical exfoliation method, in which two graphite rods are used as electrodes. The electrolyte used is a combination of citric acid and alkali hydroxide in water. Four types of quantum dots, GQD1-GQD4, are prepared by varying alkali hydroxide concentration in the electrolyte, while keeping the citric acid concentration fixed. Variation of alkali hydroxide concentration in the electrolyte results in the production of GOQDs. Balanced reaction of citric acid and alkali hydroxide results in the production of GQDs (GQD3). However, three variations in alkali hydroxide concentration result in GOQDs (GQD1, GQD2, and GQD4). GOQDs show tunable oxygen functional groups, which are confirmed by X-ray photoelectron spectroscopy. GQDs/GOQDs show absorption in the UV region and show excitation-dependent photoluminescence behavior. The obtained average size is 2-3 nm, as revealed by transmission electron microscopy. X-ray diffraction peak at around 10° and broad D band peak at 1350 cm-1 in Raman spectra confirm the presence of oxygen-rich functional groups on the surface of GOQDs. These GQDs and GOQDs show blue to green luminescence under 365 nm UV irradiation.
科研通智能强力驱动
Strongly Powered by AbleSci AI