Microwave-assisted synthesis of carbon dots from eggshell membrane ashes by using sodium hydroxide and their usage for degradation of methylene blue

• Published in: Journal of environmental chemical engineering Vol. 6; no. 6; pp. 7426 - 7433
• Main Authors: Jusuf, Bella Nathanael, Sambudi, Nonni Soraya, Isnaeni, Samsuri, Shafirah
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2018
• Subjects: Carbon dots; Eggshell membrane; Methylene blue degradation; pH sensor; Eggshell membrane; Carbon dots; Methylene blue degradation; pH sensor
• ISSN: 2213-3437; 2213-3437
• DOI: 10.1016/j.jece.2018.10.032

[Display omitted] •C-dots were synthesized by using microwave irradiation for 1 min.•The fluorescence intensity of C-dots was increased by increasing pH of solution.•The synthesized C-dots have an average size of 3.88 nm.•The degradation of methylene blue under sunlight by C-dots can be achieved by more than 50% for concentration less than 10 ppm. Carbon dots (C-dots) is a recent member of carbonaceous nanomaterial with particle size below 10 nm, equipped with unique fluorescent properties under UV light irradiation. Many methods for the production of C-dots have been reported by introducing carbon-rich waste. In this work, a facile and rapid method was developed to synthesize C-dots from the ashes of eggshell membrane (ESM) in sodium hydroxide solution assisted by one-step microwave irradiation. The optimum time in preparing the C-dots and the highest photoluminescence intensity are achieved for 1 min and by using 1 mol L−1 NaOH, respectively. The resulting C-dots with an average size of 3.88 ± 0.56 nm exhibited pH and NaOH solvent-dependent fluorescent behaviour in the visible light range. They are found to be able to degrade methylene blue under sunlight irradiation, with increasing degradation ranging from 26% to 43% for 5 ppm to 1 ppm concentration of methylene blue.