Site-Specific Deposition of Au Nanoparticles in CNT Films by Chemical Bonding

Abstract

T he overall electrical, thermal, and mechanical performance of networks of overlapped and crisscrossed carbon nanotubes (CNTs) (also called buckytube paper, CNT films, etc.) is largely determined by the nature of the contact at the nodeOthat is, the intersection of overlapping CNTs. To our knowledge, there has been no work to date on selective modification of the nodes in CNT networks, and we report here on such an effort, with an eye towards improving the transparent electrode performance of such networks.Transparent electrical conductors are a key component in modern technology, used in various applications 1,8,9 including, but not limited to, solar cells, flat panel displays, solid state lighting, still-image recorders, lasers, optical communication devices, electrodes in flexible electronics, and sensitive bolometers for detecting infrared radiation. Transparent conductive films (TCFs) based on CNTs are a promising candidate for potential use in all of the above applications and have been touted as a possible replacement for the currently used indium tin oxide (ITO) films. CNT films could offer a lower cost solution that is far more compatible with high volume production techniques, and, unlike metal oxide films, CNT films can be deposited with high volume roll-to-roll processes. CNT films are far more compliant than brittle metal oxide films, suggesting their use in plastic electronics and solar cells, thus offering interesting possibilities for both fundamental science and important technological areas. Random or quasi-random networks of CNTs ("CNT nets") have been made in thin film form and studied for use in applications such as those mentioned above. 1,8,9 However, application of CNT networks as thin films for TCFs has a major limitation, their relatively high electrical resistance. If the electrical conductivity of CNT nets could be significantly improved, the technological value of these thin films as transparent conductive electrodes would be enormously improved. The overall electrical resistance of CNT based TCFs is largely determined by the resistance at the crossing points (also called nodes or junctions) of the CNTs. We define the CNT network as being composed of nodes and segments. Modeling studies of networks of onedimensional elements have shown a resistivity dependence on segment length distributions and node resistances. 2 The electrical resistance at the nodes of CNT networks has been estimated through Monte Carlo modeling to be approximately 100 times larger than the quantum resistance of 6.5

Psychotriadouarrei and Geissois pruinosa, novel resources for the plant-based catalytic chemistry

“…Therefore it was interesting to examine whether the sulfate derived from P. douarrei was the result of the sulfur amino acid decomposition during the thermic treatment, which could explain the abnormal high level of sulfates. It had been 95 reported that cysteine, methionine, glutathione and proteins are thermally decomposed, at 400°C, in various gases such as H 2 O, H 2 S, CO 2 , NO 2 , SO 2 , and N 2 O 3 [16,17]. That is why we concluded that the excessive amount of sulfate measured was not a consequence of an unusual sulfur amino acid contained in the 100 plant.…”

Catalytic etching of monolayer graphene at low temperature via carbon oxidation

“…Those binding energies can be assigned to carbon vacancy, sp 2hybridized carbon, sp 3 -hybridized carbon, C-O and C=O, respectively. 42 These results mean that carbon atoms in the graphene could be etched, resulting in breaking the symmetry of sp 2 -hybridized and vacancy carbon atoms. As shown in the table, the area of sp 2 component decreased from 71.0 to 34.4% after etching.…”

Biomimetic Systems in Nanomedicine

“…The photographs of breast cancer tumors resistant to chemotherapy revealed their substantial reduction in size after treatment with the nanodiamonds-DOX complexes. 448,449 Other carbon nanomaterials as the fullerenes, carbon nanohorns, and carbon nanotubes (CNTs), have been used as carriers in drug delivery 450 due to their facile functionalization, [451][452][453] high carrier capacity, 454,455 high chemical stability, 456,457 and feasibility of incorporating both hydrophilic and hydrophobic substances. 458,459 However, important safety issues have been raised in the literature regarding their high toxicity.…”