Generation of subpicosecond terahertz pulses is observed when graphite surfaces are illuminated with femtosecond near-infrared laser pulses. The nonlinear optical generation of THz pulses from graphite is unexpected since, in principle, the material possesses a centre of inversion symmetry. Experiments with highly oriented pyrolytic graphite crystals suggest that the THz radiation is generated ...

The deposition and dissolution of sodium superoxide (NaO2) was investigated by atomic force microscopy. Rectangular prisms consisting of 8 smaller sub-structures grew from NaO2 platelets, when discharged in 0.5 M NaClO4, diethylene glycol dimethyl ether on highly ordered pyrolytic graphite. During oxidation the 8 sub-structures are conserved. Ring-like structures of Na2CO3 of 200 nm diameter re...

We developed a method of identifying the structural defects in graphitic materials by an anisotropic etching technique. Intrinsic and oxygen- or argon- plasma induced artificial defects' density and domain size can be obtained easily and precisely. It was inferred, through our investigations, that the grade ZYA highly oriented pyrolytic graphite (HOPG) sample has a better crystal quality, with ...

Carbonaceous materials have been shown to graphitize up to different levels upon heat treatment, depending on the characteristics of their defects and the temperature reached during the heat treatment. In the literature there are reports on the annealing of materials, such as thin carbon films, graphite fibers, polyparaphenylene (PPP)-basedcarbons, cup-stacked carbon nanotubes, diamond-like car...

A novel method to synthesize few layer graphene from bulk graphite by mechanical cleavage is presented here. The method involves the use of an ultrasharp single crystal diamond wedge to cleave a highly ordered pyrolytic graphite sample to generate the graphene layers. Cleaving is aided by the use of ultrasonic oscillations along the wedge. Characterization of the obtained layers shows that the ...

A new diffracted-beam monochromator has been developed for Bragg-Brentano X-ray diffractometers equipped with a linear detector. The monochromator consists of a cone-shaped graphite highly oriented pyrolytic graphite crystal oriented out of the equatorial plane such that the parafocusing geometry is preserved over the whole opening angle of the linear detector. In our standard setup a maximum w...

Specially designed five-electrode cells contained two types of mixed ionic-electronic conductor ~MIEC! lithium-insertion anodes. These were graphite or Sn1.3Al0.3Ti1.7O1.95(PO4)3 tin composite oxide ~TCO! bonded powders sandwiched between nickel mesh current collectors as working lithium-ion anodes, with Li foils on both sides as reference electrodes, outside of which were two further Li foils,...

We have electronically wired the cytochrome P450 BM3 heme domain to a graphite electrode with the use of a pyrene-terminated tether. AFM images clearly reveal that pyrene-wired enzyme molecules are adsorbed to the electrode surface. The enzyme-electrode system undergoes rapid and reversible electron transfer, displaying a standard rate constant higher than that of any other P450-electrode syste...

Interfacial water has unique properties in various functions. Here, using 4-dimensional (4D), ultrafast electron crystallography with atomic-scale spatial and temporal resolution, we report study of structure and dynamics of interfacial water assembly on a hydrophobic surface. Structurally, vertically stacked bilayers on highly oriented pyrolytic graphite surface were determined to be ordered, ...