A review of applications of plasmonic and conventional nanofluids in solar heat collection

Abstract

• The research progress of plasmonic nanofluids in recent ten years is reviewed. • Comparison of plasmonic nanofluids with conventional nanofluids. • The LSPR effect of plasmonic nanofluids enhances the light absorption. • Many factors affect the light absorption and photothermal conversion characteristics. • How to improve the light absorption properties of plasmonic nanofluids needs further discussion. With the development of solar energy utilization and nanotechnology, nanofluid heat collection has attracted significant attention. The solar plasmonic nanofluids with significant local surface plasmon resonance (LSPR) effect have exhibited superior behaviors in thermophysical properties, optical properties, and photothermal conversion efficiency. This paper reviews the research progress of plasmonic nanofluids in solar collectors and PV/T systems and compares them with conventional nanofluids for the first time. The plasmonic nanofluids exhibit excellent light absorption capacity and controllable light intensity and resonance frequency. Due to the existence of the LSPR effect, plasmonic nanofluids show significant absorption peak, which can meet the requirements of broadband solar energy absorption and have better usage value than conventional nanofluids in solar heat collection. Many factors affect the photothermal conversion efficiency of plasmonic nanofluids, such as particle size, concentration and flow rate. Using hybrid nanofluids can significantly broaden the extinction spectrum and further enhance light absorption. To clarify the specific mechanism of plasmonic nanofluids, improve their stability and make them more suitable for different types of solar heat collection, more experimental exploration is needed.