TY - JOUR
T1 - Graded-Index Fluoropolymer Antireflection Coatings for Invisible Plastic Optics
AU - Wang, Baomin
AU - Ruud, Christian J.
AU - Price, Jared S.
AU - Kim, Hoyeon
AU - Giebink, Noel C.
N1 - Funding Information:
This work was supported in part by the Advanced Research Projects Agency-Energy (ARPA-E) MOSAIC program, U.S. Department of Energy, under Award No. DE-AR0000626 and by the National Science Foundation under Grant No. CBET-1508968.
Funding Information:
*E-mail: [email protected]. ORCID Hoyeon Kim: 0000-0001-5508-8896 Noel C. Giebink: 0000-0002-3798-5830 Author Contributions B.W. designed and fabricated the coatings, carried out the reflectivity measurements, and performed the data analysis. C.J.R. assisted with fabrication and adhesion measurements, and H.K. performed the atomic force microscopy. J.S.P. helped formulate the concept, and N.C.G. supervised the work. All authors contributed in writing the manuscript. Funding This work was supported in part by the Advanced Research Projects Agency-Energy (ARPA-E) MOSAIC program, U.S. Department of Energy, under Award No. DE-AR0000626 and by the National Science Foundation under Grant No. CBET-1508968. Notes The authors declare no competing financial interest.
Publisher Copyright:
© 2019 American Chemical Society.
PY - 2019/2/13
Y1 - 2019/2/13
N2 - Plastic optics are used in an ever-expanding range of applications and yet a durable, high performance antireflection (AR) coating remains elusive for this material class. Here, we introduce a sacrificial porogen approach to produce ultralow refractive index nanoporous fluoropolymer AR coatings via thermal coevaporation of Teflon AF and the small molecule N,N′-bis(3-methylphenyl)-N,N′-diphenylbenzidine (NPD). Using this approach, we demonstrate a five-layer, step-graded AR coating that reduces the solar spectrum-averaged (400 < Î < 2000 nm) reflectance of acrylic plastic to <0.5% for incidence angles up to 40° and withstands over 3 months of outdoor rooftop exposure with minimal degradation. A trilayer coating optimized for the visible range yields luminous reflectivity down to â0.1%, effectively rendering double-side coated acrylic plastic invisible under room lighting conditions. Strong adhesion to most optical plastics, an outstanding combination of mechanical, chemical, and environmental durability, and compatibility with commercial vacuum coating systems should enable this AR technology to find widespread practical use.
AB - Plastic optics are used in an ever-expanding range of applications and yet a durable, high performance antireflection (AR) coating remains elusive for this material class. Here, we introduce a sacrificial porogen approach to produce ultralow refractive index nanoporous fluoropolymer AR coatings via thermal coevaporation of Teflon AF and the small molecule N,N′-bis(3-methylphenyl)-N,N′-diphenylbenzidine (NPD). Using this approach, we demonstrate a five-layer, step-graded AR coating that reduces the solar spectrum-averaged (400 < Î < 2000 nm) reflectance of acrylic plastic to <0.5% for incidence angles up to 40° and withstands over 3 months of outdoor rooftop exposure with minimal degradation. A trilayer coating optimized for the visible range yields luminous reflectivity down to â0.1%, effectively rendering double-side coated acrylic plastic invisible under room lighting conditions. Strong adhesion to most optical plastics, an outstanding combination of mechanical, chemical, and environmental durability, and compatibility with commercial vacuum coating systems should enable this AR technology to find widespread practical use.
UR - https://www.scopus.com/pages/publications/85061504106
UR - https://www.scopus.com/pages/publications/85061504106#tab=citedBy
U2 - 10.1021/acs.nanolett.8b03886
DO - 10.1021/acs.nanolett.8b03886
M3 - Article
C2 - 30626186
AN - SCOPUS:85061504106
SN - 1530-6984
VL - 19
SP - 787
EP - 792
JO - Nano letters
JF - Nano letters
IS - 2
ER -