Premium
A Facile Microwave Avenue to Electrochemiluminescent Two‐Color Graphene Quantum Dots
Author(s) -
Li LingLing,
Ji Jing,
Fei Rong,
Wang ChongZhi,
Lu Qian,
Zhang JianRong,
Jiang LiPing,
Zhu JunJie
Publication year - 2012
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.201200166
Subject(s) - graphene , electrochemiluminescence , materials science , quantum dot , quantum yield , luminescence , quenching (fluorescence) , homo/lumo , photochemistry , fluorescence , nanotechnology , optoelectronics , molecule , chemistry , physics , optics , organic chemistry , electrode
With the assistance of microwave irradiation, greenish‐yellow luminescent graphene quantum dots (gGQDs) with a quantum yield (QY) up to 11.7% are successfully prepared via cleaving graphene oxide (GO) under acid conditions. The cleaving and reduction processes are accomplished simultaneously using microwave treatment without additional reducing agent. When the gGQDs are further reduced with NaBH 4 , bright blue luminescent graphene quantum dots (bGQDs) are obtained with a QY as high as 22.9%. Both GQDs show well‐known excitation‐dependent PL behavior, which could be ascribed to the transition from the lowest unoccupied molecular orbital (LUMO) to the highest occupied molecular orbital (HOMO) with a carbene‐like triplet ground state. Electrochemiluminescence (ECL) is observed from the graphene quantum dots for the first time, suggesting promising applications in ECL biosensing and imaging. The ECL mechanism is investigated in detail. Furthermore, a novel sensor for Cd 2+ is proposed based on Cd 2+ induced ECL quenching with cysteine (Cys) as the masking agent.