Photoelectrochemical oxygen evolution from water by a manganese chlorophyll—liquid crystal electrode

In order to accomplish the photoelectrochemical evolution of oxygen from water, manganese chlorophyll was incorporated in a thin liquid crystal membrane attached to a platinum plate. The manganese chlorophyll—liquid crystal electrode reacted to water on visible light irradiation. The potential of the platinum markedly depended on the states of the immobilized chlorophyll. Visible light irradiation induced a negative shift in potential. The incorporation of a nematic liquid crystal was found to considerably enhance the potential shift on light irradiation. The negative potential shift accounted for the light-induced electron flow from water to the platinum phase. The photoelectrochemical reaction of the immobilized manganese chlorophyll was performed in parallel with the direct determination of the oxygen evolution. The molecular oxygen evolution was associated with the photocurrent.