Calcium aluminate electride 12CaO-7Al2O3:4e(e.g., C12A7:e-) shows promise as a low temperature electron emitter for hollow cathodes in spacecraft electric propulsion, but the material’s basic performance limits remain poorly understood, including an exact value for work function. As a supplement to a companion paper examining C12A7:eemission in a planar close-spaced diode configuration in vacuu...

To better understand how cathode performance and substrates affected communities that evolved in these reactors over long periods of time, microbial fuel cells were operated for more than 1 year with individual endproducts of lignocellulose fermentation (acetic acid, formic acid, lactic acid, succinic acid, or ethanol). Large variations in reactor performance were primarily due to the specific ...

New relations for and interrelations between the current responses of different microelectrode arrays are presented. Interdigitated microelectrode arrays (IDAs: alternating cathodes and anodes) and uniform microband electrode arrays (MEAs: only cathodes or anodes) are treated, and miniaturized systems with planar band electrodes or hemicylinder electrodes are discussed. A common basis was found...

Arc and glow discharges are defined based on their cathode processes. Arcs are characterized by collective electron emission, which can be stationary with hot cathodes (thermionic arcs), or nonstationary with cold cathodes (cathodic arcs). A brief review on cathodic arc properties serves as the starting point to better understand arcing phenomena in sputtering. Although arcing occurs in both me...

In this Account, we summarize some of our recent studies on the materials properties of the carbon nanotubes (CNTs). The focus is on single-wall carbon nanotubes (SWNTs). We describe experiments on synthesis of SWNTs with controlled molecular structures and assembly of functional macroscopic structures. In addition, we present results on the electron field emission properties of macroscopic CNT...

Few-layer V(2)O(5) nanosheets with a thickness of 2.1-3.8 nm have been successfully synthesized in this work via a simple and scalable liquid exfoliation technique. The unique nanostructure allows the high-rate transportation of lithium ions and electrons due to very short diffusion paths provided by this ultrathin thickness, resulting in Li-ion cathodes with remarkable energy and power densities.