Tunability of RF-Responses by Plasmonic Dielectric Amplification Using Branched e–-Polarizable C60-Adducts on Magnetic Nanoparticles

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• 作者：Min Wang ; Tzuyang Yu ; Loon-Seng Tan ; Augustine Urbas ; Long Y. Chiang
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：August 11, 2016
• 年：2016
• 卷：120
• 期：31
• 页码：17711-17721
• 全文大小：582K
• 年卷期：0
• ISSN：1932-7455

文摘

Three C₆₀-DPAF conjugates were synthesized with one as a linear monoadduct and two as branched or starburst multiadducts in structure for the investigation of chromophore antenna number-dependent tunability of RF-responses at 0.5–18 GHz. The effect was photoinduced by the generation of surface plasmonic resonance (SPR) at the surface of trilayered core–shell nanoparticles (NPs) consisting of a highly magnetic γ-FeO_x@AuNP core and an e^–-polarizable C₆₀-DPAF adduct-derived partially bilayered fullerosome outer shell. Observed large dielectric (permittivity) amplification phenomena, with the maximization on the starburst multiadduct-derived nanoparticles, were correlated to the photoactivation efficiency at the gold nanolayer. We hypothesized that the prolong accumulation (or trapping) of photogenerated SPR energy in the intermediate gold layer, sandwiched between the C₆₀(>DPAF-C₉)_x-derived fullerosome membrane and the highly magnetic γ-FeO_x NP core, was effectively released at the light-off stage to induce the intramolecular polarization of C₆₀-DPAF adducts. Resulting charged transient states were regarded as the origin of observed high permittivity-photoswitching effect. Similar tunability capabilities in subsequent measurements of distant monostatic and angle-dependent bistatic reflective SAR images might provide insights to RF-signal modulation in coating applications and the potential use of these nanomaterials as permittivity-photoswitching agents in RF-frequency devices.