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Green Synthesized Carbon Quantum Dots from Polianthes tuberose L. Petals for Copper (II) and Iron (II) Detection
Bipin Rooj1, Ankita Dutta1, Sahidul Islam2
1Department of Chemistry, The University of Burdwan, Golapbag, Burdwan, 713104, India.
Abstract:
In this work carbon quantum dots (CQDs) are synthesized via a simple, low cost and as well as green way using tuberose (Polianthes tuberose L.) petals as the carbon source for the first time. We have not done any surface modification to the prepared CQDs although we directly employed this as fluorescent probe for the sensitive and selective detection of Fe2+ and Cu2+ ions. Both these ions drastically quench the emission intensity of the CQDs; in case of Cu2+ ions quenched CQDs EDTA results in regaining the fluorescence property but for Fe2+ ions quenched CQDs no such effect of EDTA is found. The limit of detection (LOD) is observed to be 200 nM in case of Cu2+ which is much lower than the safe limit provided by the WHO in drinking water. Hence the CQDs prepared in this simple and low cost method may find an important role in monitoring the water quality. The quantum yield of the CQDs prepared in our method is around 3%. Transmission electron microscope shows picture of nicely shaped CQDs with average size ~ 4 nm.
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The Dot Product
Dot Product
In engineering, the dot product of any two vectors is the product of the magnitudes of the vectors and the cosine of the angle between them. It is denoted by a dot symbol between the two vectors.
Consider a vehicle pulling an object along the ground using a rope. If the rope makes an angle with the horizontal axis, the work done can be calculated using the dot product of the force applied and the object's displacement.
The dot...

