We show here that thermal imaging, a nonlithographic technique which enables printing multiple, successive layers via a dry additive process can be used in combination with tailored printable conductors in the fabrication of organic electronic devices. This method is capable of patterning a range of organic materials at high speed over large areas with micron size resolution and excellent electrical performance avoiding the solvent compatibility issues currently faced by alternative techniques. Such a dry, potentially reel-to-reel printing method may provide a practical route to realizing the expected benefits of plastics for electronics. We illustrate the viability of thermal imaging and imageable organics conductors by printing a functioning, large area ͑4000 cm 2 ͒ active matrix backplane display circuit containing several thousand transistors.

We examine the possibility of nitrogen-doped C60 fullerene (N-C60) as a cathode catalyst for hydrogen fuel cells. We use first-principles spin-polarized density functional theory calculations to simulate the electrocatalytic reactions on N-C60. The first-principles results show that an O2 molecule can be adsorbed and partially reduced on the N-C complex sites (Pauling sites) of N-C60 without any activation barrier. Through a direct pathway, the partially reduced O2 can further react with H(+) and additional electrons and complete the water formation reaction (WFR) with no activation energy barrier. In the indirect pathway, reduced O2 reacts with H(+) and additional electrons to form H2O molecules through a transition state (TS) with a small activation barrier (0.22-0.37 eV). From an intermediate state to a TS, H(+) can obtain a kinetic energy of ∼0.95-3.68 eV, due to the Coulomb electric interaction, and easily overcome the activation energy barrier during the WFR. The full catalytic reaction cycles can be completed energetically, and N-C60 fullerene recovers to its original structure for the next catalytic reaction cycle. N-C60 fullerene is a potential cathode catalyst for hydrogen fuel cells.

Polyaniline/single wall carbon nanotube composites were prepared to be used as printable conductors for organic electronics devices. We show here that the high aspect ratio of single wall carbon nanotubes enables percolation into a conducting network at extremely low nanotube concentration. The nature of the transport mechanism is revealed by the temperature dependence of the conductivity of these percolating composites. We demonstrate here that these thin composite films are printable via laser ablation with high resolution while retaining appropriate conductivity. The utility of these findings is illustrated by printing structures, which could serve as a source and drain with 7 μm channel and 2 S/cm conductivity for use in plastic transistors.

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