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Photovoltaic (PV) cells are the most efficient devices when absorbing photons with energies similar to its bandgap energy. They are therefore incapable of harvesting sub-bandgap photons in the infrared regime and experience significant thermalization losses when absorbing photons in the visible regime with energies above that of the bandgap energy. This excess heat from both regimes has a detrimental effect on the PV cellβs efficiency and lifetime due to the temperature rise. This dilemma has highlighted the need for a photovoltaic device able to utilize the excess heat generated effectively. In this work, an integrated hybrid photo-thermo-voltaic system is presented. The system is comprised of a plasmonic enhanced silicon PV cell with a nanostructure surface to increase the absorption of the visible spectrum. The cell is attached to a heavily doped silicon-based plasmonic infrared super absorber to trap the thermal/infrared portion of the spectrum, facilitating the harvesting of sub-bandgap photons and excess heat from the thermalization losses. The PV and absorber layers of the solar system can be easily fabricated with low cost due to their CMOS compatibility. This harvested heat energy is then utilized to heat the hot side of a connected thermo-electric generator (TEG), which directly convert waste energy into electric power by creating a temperature gradient across the TEG. This TEGs based on traditional semiconductor material π΅π΅ππ2ππππ3. Radiation energy near the bandgap is directly transformed to electricity by PV panel and simultaneously, infrared energy is utilized by the TEG to convert heat to electricity. Consequently, more electricity can be produced by the hybrid system than the power produced by a single PV or TE system. The system exhibits a considerable improvement in efficiency and power output when compared to a standalone PV cell or TEG owing to the utilization of the lost heat and IR solar spectrum. Promising applications of the system include energy storage and solar heating.
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