Hybrid Bio-Nanocomposites by Integrating Nanoscale Au in Butterfly Scales Colored by Photonic Nanoarchitectures
Krisztián Kertész,
Gábor Piszter,
Andrea Beck,
Anita Horváth,
Gergely Nagy,
György Molnár,
György Zoltán Radnóczi,
Zsolt Endre Horváth,
Levente Illés,
László Péter Biró
Affiliations
Krisztián Kertész
Institute of Technical Physics and Materials Science, HUN-REN Centre for Energy Research, 29-33 Konkoly Thege Miklos Street, 1121 Budapest, Hungary
Gábor Piszter
Institute of Technical Physics and Materials Science, HUN-REN Centre for Energy Research, 29-33 Konkoly Thege Miklos Street, 1121 Budapest, Hungary
Andrea Beck
Surface Chemistry and Catalysis Department, Institute for Energy Security and Environmental Safety, HUN-REN Centre for Energy Research, 29-33 Konkoly Thege Miklos Street, 1121 Budapest, Hungary
Anita Horváth
Surface Chemistry and Catalysis Department, Institute for Energy Security and Environmental Safety, HUN-REN Centre for Energy Research, 29-33 Konkoly Thege Miklos Street, 1121 Budapest, Hungary
Gergely Nagy
Surface Chemistry and Catalysis Department, Institute for Energy Security and Environmental Safety, HUN-REN Centre for Energy Research, 29-33 Konkoly Thege Miklos Street, 1121 Budapest, Hungary
György Molnár
Institute of Technical Physics and Materials Science, HUN-REN Centre for Energy Research, 29-33 Konkoly Thege Miklos Street, 1121 Budapest, Hungary
György Zoltán Radnóczi
Institute of Technical Physics and Materials Science, HUN-REN Centre for Energy Research, 29-33 Konkoly Thege Miklos Street, 1121 Budapest, Hungary
Zsolt Endre Horváth
Institute of Technical Physics and Materials Science, HUN-REN Centre for Energy Research, 29-33 Konkoly Thege Miklos Street, 1121 Budapest, Hungary
Levente Illés
Institute of Technical Physics and Materials Science, HUN-REN Centre for Energy Research, 29-33 Konkoly Thege Miklos Street, 1121 Budapest, Hungary
László Péter Biró
Institute of Technical Physics and Materials Science, HUN-REN Centre for Energy Research, 29-33 Konkoly Thege Miklos Street, 1121 Budapest, Hungary
Plasmonic metallic nanoparticles, like Au, can be used to tune the optical properties of photonic nanoarchitectures occurring in butterfly wing scales possessing structural color. The effect of the nanoscale Au depends on the location and the amount deposited in the chitin-based photonic nanoarchitecture. The following three types of Au introduction methods were compared regarding the structural and optical properties of the resulting hybrid bio-nanocomposites: (i) growth of Au nanoparticles inside the nanopores of butterfly wing scales by a light-induced in situ chemical reduction of HAuCl4 in aqueous solution containing sodium citrate, as a new procedure we have developed, (ii) drop-drying of the aqueous Au sol formed during procedure (i) in the bulk liquid phase, and (iii) physical vapor deposition of Au thin film onto the butterfly wing. We investigated all three methods at two different Au concentrations on the wings of laboratory-bred blue-colored male Polyommatus icarus butterflies and characterized the optical properties of the resulting hybrid bio-nanocomposites. We found that the drop-drying and the in situ growth produced comparable redshift in the spectral position of the reflectance maximum associated with the chitin-based photonic nanoarchitecture in the wing scales, while the 5 nm or 15 nm thick Au layers vacuum deposited onto the butterfly wing behaved like an optical filter, without inducing spectral shift. The in situ growth in the photonic nanoarchitecture under intense illumination produced uniform Au nanoparticles located in the pores of the biological template, which is more advantageous for further applications. An additional benefit of this method is that the Au nanoparticles do not aggregate on drying, like in the case of drop-drying of preformed Au nanoparticles from the citrate-stabilized sol.
