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arXiv · 1310.3925

A Vertical Architecture for Increasing Photogalvanic Solar Cell Efficiency: Theory and Modeling

Mohammad Ali Mahmoudzadeh·John D. W. Madden
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Abstract

Photogalvanic solar cells, the original dye based solar cell, have yet to fulfill their promise as a low fabrication cost, scalable energy conversion system. The efficient performance of photogalvanic cells relies on high dye solubility and selective electrodes with fast electron transfer kinetics. A new configuration is proposed for the photogalvanic cells that removes these impractical requirements. Instead of illuminating the device through the electrode, as is the conventional approach, a new vertical configuration is employed with light coming between the two electrodes. This way, the light absorption and hence electron generation is spread through the depth of the device. As a result, unreasonably fast electrode kinetics are no longer required. The depth can be adjusted according to the concentration of the dyes, and thus deeper cells enable low solubility dyes to be employed. The proposed configuration is mathematically modeled and the advantages over the conventional cell are shown. A numerical model is built for more detailed analysis that gives practical guidelines for working towards device parameters with high power conversion efficiency. The analysis suggests that upon the realization of highly selective electrodes and an improved dye/mediator couple, an efficiency of 13% should be achievable from the new configuration.

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Mohammad Ali Mahmoudzadeh, John D. W. Madden. 2014-09-15. A Vertical Architecture for Increasing Photogalvanic Solar Cell Efficiency: Theory and Modeling. https://doi.org/10.1016/j.electacta.2014.07.124

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