Carbon quantum dots displaying dual-wavelength photoluminescence and electrochemiluminescence prepared by high-energy ball milling

摘要

Carbon quantum dots (CQDs) with multiple surface states were prepared by high-energy ball milling a mixture of activated carbon and KOH, followed by ultrafiltration purification. The as-prepared CQDs exhibit dual-wavelength photoluminescence emission peaks. Most interestingly, the first emission peak is independent of excitation wavelength (lambda(ex)) and the second one is dependent on kex and red shifts monotonically with increasing lambda(ex). Meanwhile, the as-prepared CQDs also present dual-wavelength electrochemiluminescence property. (C) 2015 Elsevier Ltd. All rights reserved.