Full-spectrum volumetric solar thermal conversion via graphene/silver hybrid plasmonic nanofluids

Full-spectrum volumetric solar thermal conversion via graphene/silver hybrid plasmonic nanofluids

Mehrali, M. (TU Delft Energy Technology)
Ghatkesar, M.K. (TU Delft Micro and Nano Engineering)
Pecnik, R. (TU Delft Energy Technology)

2018

The wide-spread adoption of solar thermal absorbers is currently hampered by their low absorption efficiencies and their high capital cost. As a result, a number of initiatives, including direct absorption solar collectors (DASC), are currently underway to improve the absorber efficiencies. In this regard, this study focused on application of hybrid nanofluids containing reduced graphene oxides decorated with silver nanoparticles in volumetric solar absorbers. Their superior solar absorptance and thermal conductivity is based on the plasmonic effect of the nanoparticles and high thermal conductivity of graphene nanosheets, respectively. Several parameters such as mass concentration of graphene nanosheets and Ag decoration contents were studied that could affect the thermal and optical properties of the nanofluids. The results indicated that the prepared nanofluids can be employed for direct absorption solar collectors over a short period of solar irradiation time, even at a low illumination intensity of one sun. A collector efficiency of 77% is achievable at low concentration of 40 ppm owing to the enhanced light absorption of graphene at the excitation wavelength. These findings therefore suggest that this solution can contribute to the final goal of utilizing nanofluids for efficient solar thermal energy harvesting.

Direct absorption solar collectors
Graphene nanofluid
Optical properties
Plasmonic nanofluid
Solar absorption

http://resolver.tudelft.nl/uuid:05d24c8d-f3a9-4578-98db-17d66b7f9ded

https://doi.org/10.1016/j.apenergy.2018.04.065

0306-2619

Applied Energy, 224, 103-115

Institutional Repository

journal article

© 2018 M. Mehrali, M.K. Ghatkesar, R. Pecnik