Investigation of plasmonic enhanced solar photothermal effect of Au NR@PVDF micro/nano-film

TL;DR

This study demonstrates that gold nanorods embedded in PVDF films exhibit superior solar photothermal performance compared to gold nanospheres, due to plasmonic coupling effects that enhance light absorption and heat conversion.

Contribution

The paper introduces a novel comparison of Au nanorods and nanospheres in PVDF films, highlighting the enhanced photothermal efficiency of nanorods due to plasmonic interactions.

Findings

Au NR/PVDF nanofilm shows higher photothermal efficiency than Au NS/PVDF.

Plasmonic coupling in Au NRs nanoclusters causes spectral blue-shifts and boosts heat generation.

Finite element modeling confirms the role of plasmonic interactions in performance enhancement.

Abstract

Gold nanospheres (Au NSs) and gold nanorods (Au NRs) are traditional noble metal plasmonic nanomaterials. Particularly, Au NRs with tunable longitudinal plasmon resonance from visible to the near infrared (NIR) range were suitable for high efficient photothermal applications due to extended light receiving range. In this work, we synthesized Au NRs and Au NSs of similar volume, and subsequently developed them into Au NR/PVDF and Au NS/PVDF nanofilm, both of which exhibited excellent solar photothermal performance evaluated by solar photothermal experiments. We found that Au NR/PVDF nanofilm showed higher solar photothermal performance than Au NS/PVDF nanofilm. Through detailed analysis, such as morphological characterization, optical measurement, and finite element method (FEM) modeling, we found that the plasmonic coupling effects inside the aggregated Au NRs nanoclusters contributed to the spectral blue-shifts and intensified photothermal performance. As compared to Au NS/PVDF nanofilms, Au NR/PVDF nanofilm exhibited higher efficient light-to-heat conversion rate, because of the extended light receiving range and high absorbance, as the result of strong plasmonic interactions inside nanoclusters, which was further validated by monochromatic laser photothermal experiments and FEM simulations. Our work proved that the Au NRs have huge potential for plasmonic solar photothermal applications, and are envisioned for novel plasmonic applications.