Dioxygen sensitivity of a photoexcited thin film of phthalocyanine dispersed in poly(N-vinylcarbazole)

Thin films (thickness 0,3 μm) of a mixture of phthalocyaninatozinc(II) ( 1 ) and poly(1-vinylcarbazole) ( 2 ) are prepared by coating from a solution on ITO glass. The blue coloured films are investigated in an electrochemical cell under irradiation with visible light. In the presence of dioxygen from air the films exhibit an intensive cathodic photocurrent. The action spectrum of the photocurrent corresponds to the absorption spectrum of the phthalocyanine. The results show a device which can be switched by air and visible light.