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The self-assembly on soft interface is a well-known procedure for creating highly ordered films of nanoparticles (NPs) [1]. Assembling metallic nanoparticles that possess surface plasmonic resonance (SPR) can lead to different practical applications: from energy conversion devices, such as solar cells, to smart window, the transparency of which being driven by an electric field. As recently published [2], we reported a major enhancement of the photocurrent in system comprising an aqueous photosensitizer ZnTPPc (0.1 mM) and an lipophilic electron donor Fc (1 mM) in the presence of an interfacial gold film formed by the self-assembly of citrate covered Au NPs [3] promoted by addition of methanol at the DCE/water interface. In this case, illumination of the system was at 442 nm to excite both the sensitizer and the gold film. Here, we have investigated photocurrents at different wavelengths - 460, 525, 590 and 660 nm. For this purpose, the electrochemical cell shown in Fig.1 was used. Fig. 1 Electrochemical cell in the absence of gold film. Figure 2 shows the resulting photocurrent measurements: for each wavelength two curves are presented – one for the region before the transfer of Fc+ across the interface, and the other – after. The maximum of photocurrent can be observed for pumping at the wavelength 525 nm, which corresponds to surface plasmon peak on an absorption spectrum of gold NPs and a low absorption of porphyrin itself. It means that fast energy transfer occurs during the excitation and, therefore, provides the enhancement of photocurrent. Also, a smaller photocurrent at wavelength of 560 nm (corresponded to coupling between NPs in the film) was observed. Fig. 2 Photocurrent measured for system that contains 0.1 mM ZnTPPc in water phase and 1mM Fc in organic phase at 4 different wavelengths. Insert: with black is demonstrated difference between non-enhanced and enhanced photocurrent for 460 nm. All potentials are given with correction to standard transfer potential of TMA+ ion. Therefore, presence of gold films can play significant role in photoactive systems that are studying now for hydrogen and oxygen evolution and water splitting.