A one‐pot and readily practical approach is described for the preparation of superstrong, ultrathin, free‐standing single‐walled carbon nanotube (SWNT) films. The SWNT films, with controlled thicknesses of tens to hundreds of nanometers, are prepared from commonly commercialized SWNTs via a wet process. The SWNTs could be easily transferred onto any substrates after self‐releasing from filter membranes without further treatment. The obtained films exhibit excellent performances with sheet resistance of 223 Ω sq−1 and a transparency of 90% at 550 nm was obtained. Most important is that the as‐prepared free‐standing SWNT ultrathin films showed extremely high tensile strength up to 850 MPa for only about a 20‐nm thick film, which has great significance for practical applications, for example, as flexible electrode materials. The SWNT film is used to construct a capacitive touch‐screen prototype, which has a highly sensitive and quick signal touch response.

1A nonionic surfactant, n-dodecyl glyceryl itaconate (DGI), self-assembles into bilayer membranes in water having a spacing distance of sub-micrometer in the presence of small amounts of ionic surfactants, and shows beautiful iridescent color. Ionic surfactants have great effects on this iridescent system. We have interestingly found that the iridescent color changes with time after mixing DGI and ionic surfactants and the color in equilibrium state changes greatly with changing concentration of the ionic surfactants. The time dependent color change results from the transformation of DGI aggregate structure after being mixed with ionic surfactant. It is first found that the iridescent color of this nonionic system can be changed from red to deep blue by altering the concentration of ionic surfactants added even though the total concentration of surfactant is almost constant. Such large blue shift of the iridescent color in equilibrium state cannot be fully explained by the ordinary undulation theory applied so far for this phenomenon. The flat lamellar sheets tend to curve by increasing the concentration of ionic surfactants to form separated onion-like and/or myelin-like structures. These separated structures of lamellar system result in the decrease of spacing distance between bilayer membranes because some vacant spaces necessarily appear among these structures.

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