Engineering of luminescent graphene quantum dot-gold (GQD-Au) hybrid nanoparticles for functional applications

Shikha Wadhwa,Alishba T John,Ashish Mathur,Manika Khanuja,Gourav Bhattacharya,Susanta S Roy,Sekhar C Ray

doi:10.1016/j.mex.2020.100963

Shikha Wadhwa, Alishba T John + Show 5 more

Open Access

https://doi.org/10.1016/j.mex.2020.100963

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Abstract

Graphene quantum dots (GQDs) possess excellent optical and electrical properties that can be used in a wide variety of application. Synthesis of hybrid nanoparticles with GQDs have been known to improve the properties further. Therefore, in this method, graphene quantum dots –gold (GQD-Au) hybrid nanoparticles were synthesized using GQDs which reduces HAuCl4.3H2O to Au nanoparticles on its surface at room temperature. The GQDs with self-passivated layers were synthesized by microwave assisted hydrothermal method using glucose as a single precursor. The synthesis process does not involve the use of harmful chemicals. The whole synthesis process of GQD and GQD-Au hybrid nanoparticles takes only five minutes. The synthesized GQDs have been extracted using citrate in order to increase the stability of the hybrid nanoparticles for up to four weeks. The size of the synthesized GQD-Au hybrid nanoparticles is in the range of 5–100 nm and were found to be luminescent under UV-A illumination. The merit of the following method over other synthesis techniques include its rapidity, ease of preparation, and no requirement of elaborate synthesis procedures and/or harmful chemicals. The GQD-Au hybrid nanoparticles can be used in several applications such as luminescent coatings for glass and windowpanes for automobiles, etc. The reducing property of GQDs can further be utilized for the reduction of various metal salts (AgNO3) and organic dyes (methylene blue and methyl orange).. It presents a method/protocol-development of the luminescent GQD-Au hybrid particles of size ~ 5–100 nm.. The GQD-Au hybrid particles find potential applications in luminescent coating applications.

Highlights

BackgroundThe concept of quantum dots has been making rounds in the scientific community since 1980; it was only after a decade that researchers were able to synthesize successfully size tunable QDs [1,2]
Scientists have been recently attracted towards graphene QDs (GQDs) mainly because of its tunable bandgap properties in addition to pronounced quantum confinement, good electron mobility, chemical stability and edge effects leading to its application in multiple arenas [3,4,5]
Depending on the technique employed for its preparation, reports have concluded that GQDs can have a size ranging between 1 and 60 nm that synthesized at higher temperature [6]

Summary

Method Article

Engineering of luminescent graphene quantum dot-gold (GQD-Au) hybrid nanoparticles for functional applications ✩. Synthesis of hybrid nanoparticles with GQDs have been known to improve the properties further In this method, graphene quantum dots –gold (GQD-Au) hybrid nanoparticles were synthesized using GQDs which reduces HAuCl4.3H2O to Au nanoparticles on its surface at room temperature. ✩ Article information method name: A facile microwave assisted hydrothermal method, using glucose as a single precursor without any harmful chemicals. Method name: A facile room temperature microwave assisted hydrothermal method Keywords: GQD-Au, Reduction of metal salts and organic dyes, Wastewater treatment Article history: Received 30 March 2020; Accepted 8 June 2020; Available online 17 June 2020. Environmental and biological science Luminescent coatings and waste water treatment A facile room temperature microwave assisted hydrothermal method R.

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Method implementation and outputs