1. |
- Eskilson, Olof, 1992-, et al.
(author)
-
Self-Assembly of Mechanoplasmonic Bacterial Cellulose-Metal Nanoparticle Composites
- 2020
-
In: Advanced Functional Materials. - : Wiley-VCH Verlagsgesellschaft. - 1616-301X .- 1616-3028. ; 30:40
-
Journal article (peer-reviewed)abstract
- Nanocomposites of metal nanoparticles (NPs) and bacterial nanocellulose (BC) enable fabrication of soft and biocompatible materials for optical, catalytic, electronic, and biomedical applications. Current BC-NP nanocomposites are typically prepared by in situ synthesis of the NPs or electrostatic adsorption of surface functionalized NPs, which limits possibilities to control and tune NP size, shape, concentration, and surface chemistry and influences the properties and performance of the materials. Here a self-assembly strategy is described for fabrication of complex and well-defined BC-NP composites using colloidal gold and silver NPs of different sizes, shapes, and concentrations. The self-assembly process results in nanocomposites with distinct biophysical and optical properties. In addition to antibacterial materials and materials with excellent senor performance, materials with unique mechanoplasmonic properties are developed. The homogenous incorporation of plasmonic gold NPs in the BC enables extensive modulation of the optical properties by mechanical stimuli. Compression gives rise to near-field coupling between adsorbed NPs, resulting in tunable spectral variations and enhanced broadband absorption that amplify both nonlinear optical and thermoplasmonic effects and enables novel biosensing strategies.
|
|
2. |
- Guell-Grau, Pau, et al.
(author)
-
Elastic Plasmonic-Enhanced Fabry-Perot Cavities with Ultrasensitive Stretching Tunability
- 2022
-
In: Advanced Materials. - : WILEY-V C H VERLAG GMBH. - 0935-9648 .- 1521-4095. ; 34:7
-
Journal article (peer-reviewed)abstract
- The emerging stretchable photonics field faces challenges, like the robust integration of optical elements into elastic matrices or the generation of large optomechanical effects. Here, the first stretchable plasmonic-enhanced and wrinkled Fabry-Perot (FP) cavities are demonstrated, which are composed of self-embedded arrays of Au nanostructures at controlled depths into elastomer films. The novel self-embedding process is triggered by the Au nanostructures catalytic activity, which locally increases the polymer curing rate, thereby inducing a mechanical stress that simultaneously pulls the Au nanostructures into the polymer and forms a wrinkled skin layer. This geometry yields unprecedented optomechanical effects produced by the coupling of the broad plasmonic modes of the Au nanostructures and the FP modes, which are modulated by the wrinkled optical cavity. As a result, film stretching induces drastic changes in both the spectral position and intensity of the plasmonic-enhanced FP resonances due to the simultaneous cavity thickness reduction and cavity wrinkle flattening, thus increasing the cavity finesse. These optomechanical effects are exploited to demonstrate new strain-sensing approaches, achieving a strain detection limit of 0.006%, i.e., 16-fold lower than current optical strain-detection schemes.
|
|