Superhydrophobic carbon nanotube electrode produces a near-symmetrical alternating current from photosynthetic protein-based photoelectrochemical cells

The construction of protein-based photoelectrochemical cells that produce a variety of alternating currents in response to discontinuous illumination is reported. The photovoltaic component is a protein complex from the purple photosynthetic bacterium Rhodobacter sphaeroides which catalyses photochemical charge separation with a high quantum yield. Photoelectrochemical cells formed from this protein, a mobile redox mediator and a counter electrode formed from cobalt disilicide, titanium nitride, platinum, or multi-walled carbon nanotubes (MWCNT) generate a direct current during continuous illumination and an alternating current with different characteristics during discontinuous illumination. In particular, the use of superhydrophobic MWCNT as the back electrode results in a near symmetrical forward and reverse current upon light on and light off, respectively. The symmetry of the AC output of these cells is correlated with the wettability of the counter electrode. Potential applications of a hybrid biological/synthetic solar cell capable of generating an approximately symmetrical alternating current are discussed. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fabrication and electrical characteristics of carbon nanotube-based microcathodes for use in a parallel electron-beam lithography system

The development of the Nanolith parallel electron-beam writing head was discussed. The fabrication and electrical characteristics of carbon nanotube-based microcathodes for use in the lithographic system were described. The microcathode exhibited a peak current of 10.5 μA at 48 V when operated with a duty cycle of 0.5 percent.

Characteristics of multiwalled carbon nanotube nanobridges fabricated by poly(methylmethacrylate) suspended dispersion

Transport measurements were performed on individual PECVD grown MWCNT nanobridge structures. Temperature dependent conductance measurements show that as the temperature is decreased, the conductance also decreases. The nanotubes were able to carry high current densities with the observed maximum at ∼108 A/cm2. High volatile measurements reveal that the PECVD grown MWCNTs break down in segments of nanotube shells.