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In this review, we begin with a brief discussion of the operating principles and scientific/technical challenges faced by the development of lithium/sulfur cells. We then introduce some recent progress in exploring cathodes, anodes, and electrolytes for lithium/sulfur cells. In particular, several effective strategies used to enhance energy/power density,(More)
We present a novel fabrication method for incorporating nanometer to micrometer scale few-layer graphene (FLG) features onto substrates with electrostatic exfoliation. We pattern highly oriented pyrolytic graphite using standard lithographic techniques and subsequently, in a single step, exfoliate and transfer-print the prepatterned FLG features onto a(More)
Probe-based memory devices using ferroelectric media have the potential to achieve ultrahigh data-storage densities under high write-read speeds. However, the high-speed scanning operations over a device lifetime of 5-10 years, which corresponds to a probe tip sliding distance of 5-10 km, can cause the probe tip to mechanically wear, critically affecting(More)
Lithium/sulfur (Li/S) cells are receiving significant attention as an alternative power source for zero-emission vehicles and advanced electronic devices due to the very high theoretical specific capacity (1675 mA·h/g) of the sulfur cathode. However, the poor cycle life and rate capability have remained a grand challenge, preventing the practical(More)
In our effort to develop agents for the treatment of influenza, a phenotypic screening approach utilizing a cell protection assay identified a series of azaindole based inhibitors of the cap-snatching function of the PB2 subunit of the influenza A viral polymerase complex. Using a bDNA viral replication assay (Wagaman, P. C., Leong, M. A., and Simmen, K. A.(More)
We synthesized Fe(3)O(4) nanoparticle/reduced graphene oxide (RGO-Fe(3)O(4)) nanocomposites and evaluated their performance as anodes in both half and full coin cells. The nanocomposites were synthesized through a chemical co-precipitation of Fe(2+) and Fe(3+) in the presence of graphene oxides within an alkaline solution and a subsequent high-temperature(More)
Direct deposition of graphene on various dielectric substrates is demonstrated using a single-step chemical vapor deposition process. Single-layer graphene is formed through surface catalytic decomposition of hydrocarbon precursors on thin copper films predeposited on dielectric substrates. The copper films dewet and evaporate during or immediately after(More)
The loss of sulfur cathode material as a result of polysulfide dissolution causes significant capacity fading in rechargeable lithium/sulfur cells. Here, we use a chemical approach to immobilize sulfur and lithium polysulfides via the reactive functional groups on graphene oxide. This approach enabled us to obtain a uniform and thin (around tens of(More)
Photoelectrochemical (PEC) solar water splitting represents a clean and sustainable approach for hydrogen (H2) production and substantial research are being performed to improve the conversion efficiency. Hematite (α-Fe2O3) is considered as a promising candidate for PEC water splitting due to its chemical stability, appropriate band structure, and(More)
Scattering mechanisms in graphene are critical to understanding the limits of signal-to-noise ratios of unsuspended graphene devices. Here we present the four-probe low-frequency noise (1/f) characteristics in back-gated single layer graphene (SLG) and bilayer graphene (BLG) samples. Contrary to the expected noise increase with the resistance, the noise for(More)