NMR Detection of Single-Walled Carbon Nanotubes in Solution

通讯作者地址: Sun,YP(通讯作者),Clemson Univ, Dept Chem, Clemson, SC 29634 USA 地址: 1. Clemson Univ, Dept Chem, Clemson, SC 29634 USA 2. Clemson Univ, Lab Emerging Mat & Technol, Clemson, SC 29634 USAThe detection of nanotube carbons in solution by C-13 NMR is reported. The highly soluble sample was from the functionalization of C-13-enriched single-walled carbon nanotubes (SWNTs) with diamineterminated oligomeric poly(ethylene glycol) (PEG(1500N)). The ferromagnetic impurities due to the residual metal catalysts were removed from the sample via repeated magnetic separation. The nanotube carbon signals are broad but partially resolved into two overlapping peaks, which are tentatively assigned to nanotube carbons on semiconducting (upfield) and metallic (downfield) SWNTs. The solid-state NMR signals of the same sample are similarly resolved. Mechanistic and practical implications of the results are discussed

Solubilization of boron nitride nanotubes

通讯作者地址: Sun, YP (通讯作者), Clemson Univ, Dept Chem, Clemson, SC 29634 USA 地址: 1. Clemson Univ, Dept Chem, Clemson, SC 29634 USA 2. Clemson Univ, Lab Emerging Mat & Technol, Clemson, SC 29634 USA 电子邮件地址: [email protected] successful attempt in the functionalization and solubilization of boron nitride nanotubes is reported, and a functionalization mechanism based on interactions of amino functional groups with nanotube surface borons is proposed

Diminished Band-Gap Transitions of Single-Walled Carbon Nanotubes in Complexation with Aromatic Molecules

通讯作者地址: Sun, YP (通讯作者), Clemson Univ, Howard L Hunter Chem Lab, Dept Chem, Clemson, SC 29634 USA 地址: 1. Clemson Univ, Howard L Hunter Chem Lab, Dept Chem, Clemson, SC 29634 USAThe near-IR absorption spectrum of semiconducting single-walled carbon nanotubes is characterized by the transitions associated with the first (S11) and second (S22) pairs of van Hove singularities in the electronic density of states. We report that a significant effect on the transitions can be caused by non-covalent complexation of the nanotube with planar aromatic molecules such as pyrenes in solution, resulting in the absence of S11 and S22 bands in the near-IR absorption spectrum. Since the complexation is reversible, the characteristic absorption bands can be turned on and off with the complexation in a reversible fashion

Carbon dots for multiphoton bioimaging

通讯作者地址: Sun, YP (通讯作者), Clemson Univ, Dept Chem, Clemson, SC 29634 USA 地址: 1. Clemson Univ, Dept Chem, Clemson, SC 29634 USA 2. Clemson Univ, Lab Emerging Mat & Technol, Clemson, SC 29634 USA 电子邮件地址: [email protected] nanoparticles upon simple surface passivation exhibit bright photoluminescence. Reported here is a new finding that these carbon dots are also strongly two-photon luminescent with pulsed laser excitation in the near-infrared. The experimentally measured two-photon absorption cross-sections are comparable to those of the high-performance semiconductor quantum dots already available in the literature. The two-photon luminescence microscopy imaging of human breast cancer cells with internalized carbon dots is demonstrated

Quantum-sized carbon dots for bright and colorful photoluminescence

通讯作者地址: Sun, YP (通讯作者), Clemson Univ, Dept Chem, Clemson, SC 29634 USA 地址: 1. Clemson Univ, Dept Chem, Clemson, SC 29634 USA 2. Clemson Univ, Lab Emerging Mat & Technol, Clemson, SC 29634 USA 电子邮件地址: [email protected]