Fluorescence Spectroscopy of Gel-Immobilized Single-Wall Carbon Nanotubes with Microfluidic Control of the Surfactant Environment

详细信息    查看全文

• 作者：Felix F. Bergler ; Friedrich Sch枚ppler ; Frank K. Brunecker ; Michael Hailman ; Tobias Hertel
• 刊名：The Journal of Physical Chemistry C
• 出版年：2013
• 出版时间：June 27, 2013
• 年：2013
• 卷：117
• 期：25
• 页码：13318-13323
• 全文大小：315K
• 年卷期：v.117,no.25(June 27, 2013)
• ISSN：1932-7455

文摘

We describe the design and use of a microfluidic fluorescence cell for nanoparticle spectroscopy. The cell allows for microfluidic control of solvent and surfactant environments to study interfacial processes of nanoscale systems. We present a spectroscopic investigation on the effect of surfactant type and concentrations on the first subband exciton transition of (6,5) single-wall carbon nanotubes (SWNTs). SWNT fluorescence here serves as a surface-sensitive probe of changes at the surfactant鈥搉anotube interface. The experiments show that a displacement of H₂O or of adsorbed DNA by sodium cholate from solution leads to a pronounced blue-shift of exciton emission features and a roughly 5-fold increase of photoluminescence (PL) intensities. This is due to a combination of physical and chemical interactions. The major contribution to changes in PL quantum yield and exciton peak position can be attributed to changes in dielectric screening and its effect on exciton oscillator strengths.