[Dolphinsiu]

In my lecture notes, it says that fluorescence emission decay at a faster rate when compared with phosphorescence emission.
       O              O
       ll               ll
Ph - C - O - O - C - Ph + 2H2O2 ---> 2Ph - OH + O - C = O
                                                                    l     l
                                                                    O - C = O

                                                                       (I)

I + F(fluorescencing agent) --> F*(excited) + CO2

F* --> F + hv

But why fluorescent tube that we use in Mid-Autumn Festival can last longer (and even one day)?

[ARGOS++]

Dear Dolphinsiu,

You “intermix” two “reaction systems” which have only the last process step in common, - The Fluorescence!

And second you have forgotten that Fluorescence and Phosphorescence start not from the same excited state of the molecule!

But let’s draw a Picture: In the Spectrometer you detect Fluorescence as long as your Molecule absorbs Light of enough Energy (= short Wavelength), even for two hours if your Light-source is turned on for two hours. As soon as you turn off your Light-source, the decay starts, and ends after picoseconds till several milliseconds.
In this process we used Light as our Energy-source to populate the excited State called S₁.
During your Festival you used a chemical Reaction as Energy-source for the population, and as long as the Reaction was delivering enough Energy for Excitation, you was able to recognise Fluorescence, but that time interval is only the result of the chemical Reaction and has noting in common with its decay.
On the other hand you may know that absorbing Light to reach the first excited State goes from S₀ to the S₁ State. Precisely from this State the Fluorescence starts and ends at S₀ State.

But for Phosphorescence your molecule needs, after reaching the S₁ State, to invert the spin of the excited electron, to reach the so called “Triplett” State T₁, before the Phosphorescence is able to start.
But this inversion requires some time, and that’s the cause, for the much longer decay process.
Apropos:     Also the Phosphorescence you can observe, as long as your Energy-source for Excitation is turned on (plus one decay!).

I hope this may be of any help to you.

Good Luck!
                    ARGOS⁺⁺

[Dolphinsiu]

Thank you!

[Yggdrasil]

I'm not sure that you're talking about fluorescence.  Fluorescence occurs when the absorption of a photon knocks an electron into an excited state, causing the release of a photon when the electron returns to the ground state.  Here, in essence, you are using light energy to produce light energy.

In the light-producing reaction you have shown, however, you are using chemical energy to produce light.  This is an example of chemiluminescence, not fluorescence.

[ARGOS++]

Dear Yggdrasil,

Sorry! – But you also “intermix”, but two Definition in the wrong way.

“Chemiluminescence” is only a special case of Fluorescence, because later is defined as the Light-radiating transition of the excited Electron back to the S₀ Ground-State!

As not only by Thumb-Rule the start point for the radiation is the S₁ State, it doesn’t matter, how you reach the S₁ State of your Electron.

Quintessence:   “Chemiluminescence” is only the include of the kind of excitation into an other, separated Definition.

Maybe studying the “Jablonsky-Diagram” can be very helpful, too.

Good Luck!
                    ARGOS⁺⁺