Organic solar cells and physics education

This paper explains the operational principles of a home-made organic solar cell with the representation of an electron-cycle on an energy-level diagram. We present test data for a home-made organic solar cell which operates as a galvanic cell and current source in an electrical circuit. To determine the maximum power of the cell, the optimal current was estimated with a linear approximation. Using different light sources and dyes, the electrical properties of organic solar cells were compared. The solar cells were studied by looking at spectrophotometric data from different sensitizer dyes, generated by a do-it-yourself diffraction grating spectroscope. The sensitizer dyes of solar cells were tested by the diffraction grating spectroscope. The data were analysed on a light-intensity−wavelength diagram to discover which photons were absorbed and to understand the colours of the fruits containing these dyes. In terms of theoretical applications, the paper underlines the analogous nature of organic solar cells, a conventional single p−n junction solar cell and the light-dependent reactions of photosynthesis, using energy-level diagrams of electron-cycles. To conclude, a classification of photon−electron interactions in molecular systems and crystal lattices is offered, to show the importance of organic solar cells. (paper)