Details

Autor(en) / Beteiligte

• Pramanik, A.
• Biswas, S.
• Kumbhakar, P.

Titel

Solvatochromism in highly luminescent environmental friendly carbon quantum dots for sensing applications: Conversion of bio-waste into bio-asset

Ist Teil von

• Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, 2018-02, Vol.191, p.498-512

Ort / Verlag

England: Elsevier B.V

Erscheinungsjahr

2018

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Recently studies on synthesis and fluorescence based sensing in biocompatible carbon quantum dots (CQDs) have become a widely spoken topic of research due to the several advantageous properties of CQDs in compared to semiconductor quantum dots. In this work, we have reported the rarely reported solvatochromism along-with a high photoluminescence (PL) quantum yield (PLQY) of 22%. Samples have been synthesized by using a simple process of hydrothermal carbonization of a naturally occurring bio-waste i.e. Aegle marmelos leaves powder. The linear absorption and PL emission characteristics of CQDs have been studied in different solvent environments to explore the origin of the observed excitation dependent PL emissions characteristics of the sample. The interesting solvatochromic PL (SPL) behavior of CQDs are observed at an excitation wavelength of 325nm by dispersing them in different polar protic and aprotic solvents, which suggest their possible applications as a replacement of solvatochromic dye molecules for sensing applications. Different polarity functions and molecular-microscopic solvent polarity parameter (ETN) are used to calculate the change in dipole moment (Δδ) of the solute-solvent system and the origin of SPL in CQDs has been explained. The SPL behavior of CQDs has been utilized for fluorescence sensing of organic liquids (Ethanol and Tetrahydrofuran) in water. Whereas, the photo-induced electron transfer mediated quenching in PL of aqueous dispersion of CQDs has led to development of “turn off” fluorescence Fe3+ ion sensor with a detection limit of 0.12μM. Therefore, this work may open a new avenue of conversion of a bio-waste into a fluorescent bio-asset. [Display omitted] •Solvatochromic PL (SPL) emission in fluorescent CQDs synthesized from bio-waste, namely Aegle marmelos leaves powder.•Development of flexible luminescence system for intensity modulated bluelight emission in solvents of diverse polarities.•The SPL emissive property of CQDs has been used for sensing of organicliquids (ethanol and tetrahydrofuran) in water.•Development of fluorescent Fe3+ ion sensor with a detectionlimit of 0.12µM via PET mediated PL quenching in CQDs.