Enhanced optical limiting in functionalized hydrogen exfoliated graphene and its metal hybrids
| Autor: | Adarsh Kaniyoor, Benoy Anand, Sundara Ramaprabhu, S. Siva Sankara Sai, Reji Philip |
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| Jazyk: | angličtina |
| Rok vydání: | 2013 |
| Předmět: |
Nonlinear absorptions
Materials science Inter-band transition Analytical chemistry Luminescence of organic solids Physics::Optics Nanoparticle Metal nanoparticles Photochemistry Light scattering law.invention symbols.namesake Two-photon absorptions Charge transfer law Materials Chemistry Light absorption Hydrogen exfoliated graphene Absorption (electromagnetic radiation) Semiconductor quantum wells Graphene Saturable absorption General Chemistry Nanosecond Two photon processes Thermally induced Metals Femtosecond Excited state absorption symbols Raman spectroscopy Hydrogen Excitation regime |
| Zdroj: | IndraStra Global. |
| ISSN: | 2381-3652 |
| Popis: | We present the mechanism and performance of optical limiting (OL) in hydrogen exfoliated graphene (HEG), functionalized HEG (f-HEG) and its metal hybrids. At the wavelengths used, the mechanism of nonlinear absorption (NLA) involves two-photon absorption and excited state absorption in the nanosecond excitation regime, and saturable absorption in combination with two-photon absorption in the femtosecond (ultrafast) excitation regime. The role of defects in the OL performance of HEG and f-HEG is investigated with the help of their Raman spectra. OL efficiency of f-HEG is found to improve with Pt and Pd nanoparticle decoration due to an enhanced NLA, which arises mainly from interband transitions between the d band and the s-p conduction band in the metal NPs, and charge transfer between f-HEG and metal NPs. Thermally induced light scattering is negligible in these water dispersed systems. � 2013 The Royal Society of Chemistry. |
| Databáze: | OpenAIRE |
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