6/20/2014 Synthesis of nanocomposite thin films with tunable optical properties Naoufal Bahlawane Introduction Carbon, Metal, metal carbide or metal oxide nanoparticles Metal oxide, metal nitride or organic-inorganic hybrid matrix Nanocomposite thin film Tuning parameters: Nanoparticles: - Chemical nature - Size - Density Matrix: - Composition - Porosity/ density Dr. N. Bahlawane 19 June 2014 1 6/20/2014 Plasmonic Color Development of decorative coatings with highly adjustable optical appearance: - Distinct and attractive colors - An appearance that is insensitive to the: - surface roughness - thickness - nature of the underlying substrate materials - Resistance to chemical/mechanical and thermal aggressions Using an appropriate process: - The synthesis does not involve the manipulation of nanoparticles (in situ formation) - The integration ability (thermal budget, chemical compatibility, 3D object coatings…) - Up scaling ability of the process Dr. N. Bahlawane 19 June 2014 Content • Synthesis process – The general view – The implementation – The proof of principle – Ag-ZnO – Ni-ZnO – Alloys-ZnO – Statements • Tunable optical properties – – – – Background Simulation Experimental state of the art Statements Dr. N. Bahlawane 19 June 2014 2 6/20/2014 Metal-Organic Chemical Vapor Deposition MOCVD Dr. N. Bahlawane 19 June 2014 Synthesis process Chemical Vapor Deposition Flow direction Nucleation Homogeneous reaction Desorption of the by-products Diffusion to the surface Desorption Surface diffusion Surface adsorption Surface reaction Nucleation CVD of Compound Semiconductors, Jones /O'Brien VCH, 1997 Dr. N. Bahlawane 19 June 2014 3 6/20/2014 The implementation Semi-industrial facility in clean-room Laboratory Φ = 200mm Home-made Lab facility Φ = 150mm Dr. N. Bahlawane 19 June 2014 Nanocomposites: Ag-ZnO Ag-ZnO film ZnO matrix Ag nanoparticle A g (1 1 1 ) A g -Z n O Z n O Substrate Dr. N. Bahlawane 3 0 3 5 40 2 Θ 45 5 0 5 5 60 6 5 /d e g re e 19 June 2014 4 6/20/2014 Ni-ZnO film Nanocomposites: Ni-ZnO 5 nm XRD: Ni (hcp) D= 4.4 nm Substrate TEM: D= 2-4 nm Dr. N. Bahlawane 19 June 2014 Other examples XPS XRD Cu0.34Ni0.66-ZnO Cu (111); (200) Intensity / a. u. Cu-ZnO Ni (002) (011) Ni-ZnO Ag (111) Ag-ZnO ZnO 30 35 40 45 50 55 60 65 Materials Particle size /nm Density / cm3 Ni-ZnO 4.4 1.9 1018 Cu-ZnO 11.6 7 1016 CuNi-ZnO 6.6 2.2 1017 2Θ / degree Dr. N. Bahlawane 19 June 2014 5 6/20/2014 Take-home message • Compatible chemistries were identified to grow oxidized and non-oxidized transition metals. • Noble and reactive metals can be incorporated into oxide matrices. • Nanoparticles can be embedded as pure metals, alloys, or as bi-phased nanoparticles. Dr. N. Bahlawane 19 June 2014 Tunable optical properties: Plasmonic colors Dr. N. Bahlawane 19 June 2014 6 6/20/2014 Plasmonics: background Light-nanoparticles interaction Light Plasmon Light The wavelength at which the resonant interaction occurs (localized Surface Plasmon Resonance: SPR) depends on various parameters: - Size of the nanoparticles - Shape of the nanoparticles - Composition of the nanoparticles - The distance between them - Refractive index of the matrix Dr. N. Bahlawane 19 June 2014 Plasmonics: background The SPR band maximum according to Mie’s theory: High-frequency dielectric constant of the nanoparticle π c ⋅ me ⋅ (ε 0 + 2n 2 λ2max = 2 ) Refractive index of the medium e2 Ne Density of free electrons on the metal nanoparticles. Dr. N. Bahlawane 19 June 2014 7 6/20/2014 Plasmonic: Simulation Effect of the size of the nanoparticles: 1.0 Intensity (a. u. ) 0.8 Refractive index of the medium: 1.45 Nanoparticles: Silver (Ag) 5 nm 10 nm 15 nm 20 nm 0.6 0.4 Effect of the nanoparticles composition: 0.2 1.0 400 500 600 Wavelength (nm) Intensity (a. u. ) 0.0 alloys 0.8 Nanoparticle size: 10 nm Refractive index of the medium: 1.45 0.6 Au Ag 0.4 0.2 0.0 400 500 600 700 800 900 Wavelength (nm) Dr. N. Bahlawane 19 June 2014 Plasmonic: Simulation Effect of the medium: Intensity (a. u. ) 1.0 0.8 Nanoparticles: 10 nm Silver (Ag), Refractive index of the medium: 0.6 1 1.45 2 2.2 0.4 0.2 0.0 300 400 500 600 700 800 900 Wavelength (nm) Effect of the distance between nanoparticles: Dr. N. Bahlawane 19 June 2014 8 6/20/2014 Experimental state-of-the-art Tuning the nano-particle Bahlawane et al: Angew. Chem. 50(2011)9957-9960 20 nm Dr. N. Bahlawane 19 June 2014 Nanocomposites: Au-TixZnOy Tuning the matrix Variation of composition Metal oxide matrix Intensity (a. u.) 1.0 Ti / (Ti+Zn) 0 0.2 0.3 0.5 0.8 0.6 0.4 0.2 0.0 400 Au‒ Ti-doped ZnO 500 600 700 800 900 Wavelength (nm) 600 590 Nanocomposite thin film SPR (nm) 580 570 560 550 540 0.0 0.1 0.2 0.3 0.4 0.5 Ti / (Ti+Zn) in the feedstock Dr. N. Bahlawane 19 June 2014 9 6/20/2014 State-of-the-art Ag-ZnO AuxAg1-x-ZnO SPR = 480 nm SPR = 530 nm Au-ZnO SPR = 650 nm Dr. N. Bahlawane 19 June 2014 Take-home message • Nanocomposite coatings can be made with tailored optical properties via: • The tuning of the nanoparticles size and density • The tuning of the nanoparticles composition • The tuning of the matrix composition • The choice of the matrix allows the combination of the decorative aspect with other properties: • • • • Dr. N. Bahlawane Mechanical resistance Chemical resistance Thermal resistance Diffusion barrier 19 June 2014 10 6/20/2014 Centre de Recherche Public - Gabriel Lippmann +352 470 261 585 [email protected] www.lippmann.lu Thank you for your attention Dr. N. Bahlawane 19 June 2014 11
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