IRREVERSIBLE ADSORPTION OF CHLOROPHYLL ON AMALGAMATED PLATINUM-ELECTRODES IN APROTIC-SOLVENTS

The adsorption of chlorophyll (Chl) was studied at controlled potential on amalgamated platinum electrodes in aprotic solvents (acetone, propylene carbonate, and gamma-butyrolactone). It was shown that Chl is strongly adsorbed, and it will only desorb from the surface at appreciable negative potentials. In the adsorption of Chl, typically one or several regions are found where the amount adsorbed is independent of the solution concentration, and depending on the adsorption conditions (concentration, potential, and solvent), several adsorbed states can exist. Adsorption probably involves a collectivization of adsorbate electrons and metal electrons.