Novel and Fast Microwave-Assisted Synthesis of Carbon Quantum Dots from Raw Cashew Gum

Journal of the Brazilian Chemical Society

Natalia R. Pires¹  Clara M. W. Santos¹  Rayane R. Sousa¹  Regina C. M. De Paula¹  Pablyana L. R. Cunha¹  Judith P. A. Feitosa¹ 

关键词: carbon quantum dots;    cashew gum;    microwave-assisted synthesis;    photoluminescence;   

DOI  :  10.5935/0103-5053.20150094

来源: SciELO

【 摘 要 】

Carbon quantum dots (C-dots) with average size of 9 nm were synthesized from an aqueous solution of raw cashew gum (RCG) using a novel and fast microwave-assisted technique which involves two steps. In the first step (partial depolymerization in solution) some monomer units are formed through the autohydrolysis of CG and a small amount of 5-hydroxymethyl furfural can be obtained. The second step involves polycondensation/polymerization to give rise to a polyfuranic structure followed by aromatization/carbonization and nuclear burst. At the end of the process a composite of partially depolymerized CG and C-dot was formed. A mechanism involved in microwave-assisted two-steps synthesis was suggested. Although no passivation reagent was used, an intensely blue photoluminescent material in UV light was obtained. C-dot was characterized by spectroscopy in the medium infrared, thermal analysis, gel permeation chromatography, transmission electron microscopy, zeta potential, and photoluminescence.

【 授权许可】

CC BY   
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