Details

Autor(en) / Beteiligte

• Chen, Kai
• Dao, Thang Duy
• Ishii, Satoshi
• Aono, Masakazu
• Nagao, Tadaaki

Titel

Infrared Aluminum Metamaterial Perfect Absorbers for Plasmon-Enhanced Infrared Spectroscopy

Ist Teil von

• Advanced functional materials, 2015-11, Vol.25 (42), p.6637-6643

Ort / Verlag

Blackwell Publishing Ltd

Erscheinungsjahr

2015

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• Matured surface chemistry and excellent chemical stability have enabled gold to become the material‐of‐choice for plasmonic sensing in both visible and infrared wavelength range. Here, successful surface functionalization of metamaterials made from a low‐cost abundant plasmonic material, aluminum, with phosphonic acid and subsequent detection of the CO vibration mode via surface‐enhanced infrared absorption spectroscopy is demonstrated. The metamaterial consists of infrared perfect absorbers fabricated by colloidal lithography. Near perfect absorption is achieved at resonance wavelengths, which can be readily tuned by changing the diameters of the Al disk resonators, enabling excellent overlapping with the molecular vibration. Separately, the detection of a physically adsorbed protein layer on the Al metamaterial is also demonstrated. Surface functionalization with phosphonic acid provides various functional groups to the Al surfaces. Combined with tunable metamaterials, the work herein opens up great opportunities for Al‐based plasmonic nanostructures for biochemical sensing applications. Infrared aluminum metamaterial perfect absorbers (MPAs) are fabricated using scalable and cost‐effective colloidal lithography and dry etching. The plasmon resonances can be readily tuned by the etching time of polystyrene spheres. Chemical surface functionalization of the MPAs is achieved using phosphonic acid making it possible to use Al for surface enhanced infrared absorption spectroscopy.