I used Rhodamine B to find the quantum yield of pyrene, but I got it wrong. I was reading some literature and it says that reference dye should resemble your dye ( expected QY and absorption band).
And I am also trying to find the quantum yield of benzopyrene.
Thanks.
Here are a few sources about measurement of fluorescence quantum yield that suggest fluorophores to use as standards, depending on the desired wavelength range.
http://www.horiba.com/fileadmin/uploads/Scientific/Documents/Fluorescence/quantumyieldstrad.pdf
http://www.iss.com/resources/pdf/technotes/Measurement_Fluorescence_Quantum_Yields.pdf
Be careful to keep the pyrene concentration low enough to avoid both inner filter effect and excimer formation. Make sure to use the same solvent for the standard that was used to measure its quantum yield.
This means if pyrene is in ethanol , its emission is between 350 nm to 460 nm . then anthracene in ethanol is the best molecule as its emission falls between 360~480 nm.
I am also keeping the absorption of pyrene ( peak at 334 nm) between 0.02~0.06 a.u to avoid the inner filter effect and excimer formation.
Thank you for your response. it is helpful. .
I appreciate it.
You find the fluorescence quantum yield (fQY) through comparison of areas of fluorescence spectra of your dye (Pyrene) and a reference dye with a known fQY. Therefore, you'd better use a reference dye with a fluorescence spectrum in the wavelength regime as Pyrene. Anthracene is one possibility, as was mentioned above. Try also Quinine sulphate (QS) in 0.1M H2SO4. In my view this is a better choice since QS as a reference is measured in acid under aqueous conditions, so no hazards of changing the concentration via evaporation,while you still do not seal the Cuvette.
Good sources.
I agree with Lerner. I would prefer quinine because it is easier to handle. Water is a less volatile solvent. Quinine is insensitive to oxygen and is photochemically more robust. You do have to make a refractive index correction ("The Measurement of Photoluminescence Quantum Yields", J. Phys. Chem. 75, 991 (1971)).
I like the good recent review
https://www.iupac.org/publications/pac/pdf/2011/pdf/8312x2213.pdf
Additionally to the comments added above, I could also point you out to the PhotoChemCAD website, where you'll find the absorption and emission spectra of many compounds (http://omlc.org/spectra/PhotochemCAD/index.html). The papers from Würth et al. (http://pubs.acs.org/doi/abs/10.1021/ac2000303 and http://www.nature.com/nprot/journal/v8/n8/abs/nprot.2013.087.html) describe the method and discuss standards covering the whole spectral region. I also agree with Lerner and will go on with Quinine Sulfate. Make sure your water is free from chloride, as Cl- is a good quencher of QS, and chek the concentration of sulfuric acid you'll use (the standard values are given in the IUPAC report quoted in the answer by Demas).
PhotochemCad is great for pulling up spectra and other information. I use it for demonstrating the Strickler Berg lifetime formula and for sample FRET calculations.
Unfortunately it is only for PCs.
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