Electronic structures of zigzag edged graphene nanoribbons (ZGNRs) doped with boron (B) or nitrogen (N) atoms are investigated by spin polarized first-principles calculations. We find that ZGNRs can be tuned to be either semiconducting, half-metallic, or metallic by controlling the distance of the impurity atoms to the edges. A new scheme is identified to achieve full half-metallicity in ZGNRs ...

We investigate spin transport in diffusive graphene nanoribbons with both clean and rough zigzag edges, and long-range potential fluctuations. The long-range fields along the ribbon edges cause the local doping to come close to the charge neutrality point forming p-n junctions with localized magnetic moments, similar to the predicted magnetic edge of clean zigzag graphene nanoribbons. The resul...

Effect of nitrogen post-doping on a commercial platinum–ruthenium/carbon anode catalyst Report Title This work investigates the effects of after-the-fact chemical modification of a state-of-the-art commercial carbonsupported PtRu catalyst for direct methanol fuel cells (DMFCs). A commercial PtRu/C (JM HiSPEC-10000) catalyst is post-doped with nitrogen by ion-implantation, where “post-doped” den...

In this work we have investigated the effects of substituting carbon atoms with B and N on the second hyperpolarizability of C60 using time-dependent density functional theory. We have calculated the second hyperpolarizability of the double substitute-doped fullerenes C58NN, C58BB and C58BN. For C60 only small changes in the second hyperpolarizability were found when doping with either 2B or 2N...

We studied the transition from the electrochemical double-layer charging regime to intercalative doping of bundled single-walled carbon nanotubes (SWNT) in KCl and HCl aqueous solution. For this purpose we used high doping levels by applying constant potentials above 1000 mV approaching and slightly exceeding the oxidation potential for Cl(-) ions. At each potential in situ Raman measurements o...

Electrical properties and annealing behaviour of undoped and doped amorphous silicon carbon nitride (a-SiC N ) thin films, x y deposited by ion beam sputtering techniques, have been studied. Doping of the a-SiC N thin films with magnesium (Mg), and x y phosphorous (P) was carried out by ion implantation techniques, and subsequent annealing effect on the electrical conductivity (s) and activatio...

Persistent currents driven by a static magnetic flux parallel to the carbon nanotube axis are investigated. Owing to the hexagonal symmetry of graphene the Fermi contour expected for a 2D-lattice reduces to two points. However the electron or hole doping shifts the Fermi energy upwards or downwards and as a result, the shape of the Fermi surface changes. Such a hole doping leading to the Fermi ...

In situ Raman experiments together with transport measurements have been carried out on carbon nanotubes as a function of gate voltage. In metallic tubes, a large increase in the Raman frequency of the G(-) band, accompanied by a substantial decrease of its linewidth, is observed with electron or hole doping. In addition, we see an increase in the Raman frequency of the G(+) band in semiconduct...

Noncovalent functionalization of boron nitride nanotubes (BNNTs) in aqueous solution was achieved by means of pi-stacking of an anionic perylene derivative, through which carboxylate-functionalized BNNTs were prepared for the first time. Starting from the functionalized nanotubes, an innovative methodology was designed and demonstrated for the controlled near-surface carbon doping of BNNTs. As ...