Chemiluminescence
“Chemiluminescence(sometimes "chemoluminescence") is the emission of light with limited emission of heat (luminescence) as the result of a chemical reaction. Given reactants A and B, with an excited intermediate ◊,
[A] + [B] →[◊] →[Products] + light
For example, if [A] is luminol and [B] is hydrogen peroxide in the presence of a suitable catalyst we have:
luminol + H2O2 →3-APA[◊] →3-APA + light
where:
- where 3-APA is 3-aminophthalate
- 3-APA[◊] is the excited state fluorescing as it decays to a lower energy level.
The decay of this excited state[◊] to a lower energy level causes light emission. In theory, one photon of light should be given off for each molecule of reactant. This is equivalent to Avagadro’s number of photons per mole of reactant. In actual practice, non-enzymatic reactions seldom exceed 1% QC, quantum efficiency. “
Recent Journal Articles
Electrogenerated Chemiluminescence of Pure Polymer Films and Polymer Blends
(598–603)Macromolecular Rapid Communications 32 #7 (2011)
Chen et al of the National Chiao Tung University, Taiwan and The University of Texas at Austi, Texas, recently reported the discovery of soliton-like electrogenerated chemiluminescence (ECL) waves from pure conjugated polymer films and gold-nanoparticles-doped polymer films. This chemiluminescence was found in polymer blends of conjugated and nonconjugated polymers. Poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8BT) is used as the active material that is oxidized and produces ECL with the presence of a co-reactant, tri-n-propylamine (TPA). When polystyrene (PS), less soluble in the electrolyte, is blended with F8BT, dotted ECL signals are observed and transported as waves. When poly(methyl methacrylate) (PMMA), more soluble in the electrolyte, is blended with F8BT, PMMA serves as local scratches and ECL waves are triggered simultaneously from the whole film. (RDC 4/5/2011)