Photonic Strategies for Photovoltaics: New Advances Beyond Optics

Ana Mouquinho, O. Sanchez-Sobrado, S. Haque, P. Centeno, M. F. Alexandre, G. Ribeiro, J. Boane, T. Mateus, U. D. Menda, HHholpsdasjashd H. Águas, E. Fortunato, R. Martins, and M. J. Mendes

Faculty of Science and Technology, University NOVA de Lisboa and CEMOP/UNINOVA, Campus de Caparica, Caparica, Portugal

Abstract: Photonic structures with dimensions comparable to sunlight wavelengths are now regarded as the preferential solutions to enhance the efficiency of photovoltaic devices via light trapping. These photonic microstructures operate in the wave-optics regime. Electromagnetic models were thus developed to determine the optimal parameters for application in the front contact of different photovoltaic technologies, namely in thin-film solar cells based in silicon or perovskite materials. In this way, distinct photonic cell architectures were obtained, showing efficiency improvements up to 50% with respect to planar reference solar cells. The results demonstrate that the advantages in the application of the photonic structures are not just limited to optical gains related with light absorption enhancement, but also enable other important benefits such as: electrical gains due to the improvement of the front contact conductance, and better environmental/outdoor performance due to an advanced micro-structured encapsulation that even allows self-cleaning properties.

Key words: solar energy, thin-film photovoltaics, photonics, light management