Monolayer Plasmonic Nanoframes as Large‐Area, Broadband Metasurface Absorbers

Abstract

Broadband absorbers are useful ultraviolet protection, energy harvesting, sensing, and thermal imaging. The thinner these structures are, the more device‐relevant they become. However, it is difficult to synthesize ultrathin absorbers in a scalable and straightforward manner. A general and straightforward synthetic strategy for preparing ultrathin, broadband metasurface absorbers that do not rely on cumbersome lithographic steps is reported. These materials are prepared through the surface‐assembly of plasmonic octahedral nanoframes (NFs) into large‐area ordered monolayers via drop‐casting with subsequent air‐drying at room temperature. This strategy is used to produce three types of ultrathin broadband absorbers with thicknesses of ≈200 nm and different lattice symmetries (loose hexagonal, twisted hexagonal, dense hexagonal), all of which exhibit efficient light absorption (≈90%) across wavelengths ranging from 400–800 nm. Their broadband absorption is attributed to the hollow morphologies of the NFs, the incorporation of a high‐loss material (i.e., Pt), and the strong field enhancement resulting from surface assembly. The broadband absorption is found to be polarization‐independent and maintained for a wide range of incidence angles (±45°). The ability to design and fabricate broadband metasurface absorbers using this high‐throughput surface‐based assembly strategy is a significant step toward the large‐scale, rapid manufacturing of nanophotonic structures and devices.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 20, 2022
Source ID
10.1002/smll.202201171

Entities

People

  • Chad Mirkin
  • Devleena Samanta
  • Koray Aydın
  • Sina Abedini Dereshgi
  • Wenjie Zhou
  • Wisnu Hadibrata
  • Yuanwei Li
  • İbrahim Tanrıöver

Organizations

  • Air Force Office of Scientific Research
  • Northwestern University
  • Office of Basic Energy Sciences
  • Office of Science
  • United States Department of Energy

Tags

Fields of Study

  • Materials science

Readers

  • Microwave Engineering.
  • Nanoscale Plasmonic Nanotechnology
  • Thin Film Deposition Science.