Spectrum splitting using gold and silver nanofluids for photovoltaic/thermal collectors

The thermal yield of hybrid photovoltaic/ thermal (PV/T) collectors is presently limited to low temperatures to prevent degradation of PV efficiency and thermal damage to the cells. This work reports a nanofluid optical filter, which transmits only the portion of the solar spectrum which is most efficiently converted to electricity by the underlying solar cell. This is achieved by suspending both core-shell silver-silica nanodiscs (Ag-SiO2 NDs) and gold nanorods (AuNRs) in an aqueous base fluid to absorb visible light and infrared wavelengths, respectively. The transmission spectrum of each nanofluid can be tailored according to PV cell spectral response and to accommodate for electricity and gas price fluctuations.