Synthesis of Fluorescent Carbon Quantum Dots from Tobacco Wastewater for the Detection of Ferric(III) Ions

Abstract

In this study, fluorescent carbon quantum dots (CQDs) are prepared using a one-step pyrolysis from tobacco wastewater. The TEM, UV-vis, XPS, FT-IR and PL techniques are employed to characterize the morphology, elementary composition and optical properties of these CQDs. It is found that the CQDs in ethanol solution can achieve strongly the blue light emission under the UV irradiation and the fluorescence quantum yield (QY) can reach up to 51.7%. Most importantly, we find that the CQDs can be applied for selective detection of Ferric(III) ions in solutions via photoluminescence (PL) measurement. The sensitivity of the detection can reach up to 0.1 M. The analysis of the electronic energy structure suggests that the quenching of the PL emission by the presence of Ferric(III) ions is attributed to the surface functional groups attached to the CQDs, which can interact with metal ions so that the electrons in the excited state of the CQDs are transferred into the unoccupied orbits of Ferric(III) ions. A corresponding physical mechanism is proposed to gain a understanding about how the presence of the Ferric(III) ions can affect the PL emission from CQDs.

Coconut Carbon Dots: Progressive Large-Scale Synthesis, Detailed Biological Activities and Smart Sensing Aptitudes towards Tyrosine

“…Being a metal free-fluorophore, carbon dots are considered to be one of the economically viable materials with high water solubility and photo-stability. The highly biocompatible nature of carbon dots has made them a useful material in biomedicines as a way of providing effective alternatives for drug delivery in chemotherapy [ 21 , 22 , 23 ]. The advanced optical and luminescence properties of carbon dots (C-dots) have demonstrated impressive potency in photocatalysis, chemosensing, light emitting diodes (LEDs) and electrochemical sensing [ 24 , 25 , 26 ].…”

Highly Sensitive and Selective Sulfite Ion Sensor Based on Biochemically Stable Iodo‐Functionalized Coumarin Fluorophores

“…The slight hyperchromic alteration was observed in the absorption spectrum (Figure 2a) which might be due to the presence of auxochromic group which possess very high tendency to capture the light and increase the absorption intensity [24–26] . On increasing the concentration of ligand D, the number of particles increases and leads to enhance the surface energy values and contribute towards optical density behavior [27,28] . From here, it can be inferred that the developed ligand D possess outstanding optical absorption behaviour and useful in sensing application.…”

“…[24][25][26] On increasing the concentration of ligand D, the number of particles increases and leads to enhance the surface energy values and contribute towards optical density behavior. [27,28] From here, it can be inferred that the developed ligand D possess outstanding optical absorption behaviour and useful in sensing application. Afterwards, fluorescence spectroscopy was utilized to evaluate the emissive-luminescent behavior of prepared lignad D (Figure 2b).…”

Recent Developments of Carbon Dots in Biosensing: A Review

“…Similar strategy has also been applied for the sensing of vitamin B12 . Considering the fact that CDs have very good specificity toward some metal ions (i.e., Cu 2+ and Fe 3+ ), , CDs are also frequently used for the sensing of trace metal elements in organisms (Figure C) . In most of the systems, metal ions are detected because their interaction with CDs could effectively quench the PL of CDs via PET.…”