Flexible thin-film black gold membranes with ultrabroadband plasmonic nanofocusing for efficient solar vapour generation

Kyuyoung Bae, Gumin Kang, Suehyun K. Cho, Wounjhang Park, Kyoungsik Kim, Willie J. Padilla

Research output: Contribution to journalArticle

290 Citations (Scopus)


Solar steam generation has been achieved by surface plasmon heating with metallic nanoshells or nanoparticles, which have inherently narrow absorption bandwidth. For efficient light-To-heat conversion from a wider solar spectrum, we employ adiabatic plasmonic nanofocusing to attain both polarization-independent ultrabroadband light absorption and high plasmon dissipation loss. Here we demonstrate large area, flexible thin-film black gold membranes, which have multiscale structures of varying metallic nanoscale gaps (0-200 nm) as well as microscale funnel structures. The adiabatic nanofocusing of self-Aggregated metallic nanowire bundle arrays produces average absorption of 91% at 400-2,500 nm and the microscale funnel structures lead to average reflection of 7% at 2.5-17 mm. This membrane allows heat localization within the few micrometre-Thick layer and continuous water provision through micropores. We efficiently generate water vapour with solar thermal conversion efficiency up to 57% at 20kWm2. This new structure has a variety of applications in solar energy harvesting, thermoplasmonics and related technologies.

Original languageEnglish
Article number10103
JournalNature communications
Publication statusPublished - 2015 Jan 1


All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Physics and Astronomy(all)

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