Fast Exfoliation and Functionalisation of Two-Dimensional Crystalline Carbon Nitride by Framework Charging.

Two-dimensional (2D) layered graphitic carbon nitride (gCN) nanosheets offer intriguing electronic and chemical properties. However, the exfoliation and functionalisation of gCN for specific applications remain challenging. We report a scalable one-pot reductive method to produce solutions of single- and few-layer 2D gCN nanosheets with excellent stability in a high mass yield (35 %) from polytriazine imide.

Hydrogen adsorption and diffusion around Si(0 0 1)/Si(1 1 0) corners in nanostructures.

While the diffusion of hydrogen on silicon surfaces has been relatively well characterized, both experimentally and theoretically, diffusion around corners between surfaces, as will be found on nanowires and nanostructures, has not been studied. Motivated by nanostructure fabrication by Patterned Atomic Layer Epitaxy, we present a density functional theory study of the diffusion of hydrogen around the edge formed by the orthogonal (0 0 1) and (1 1 0) surfaces in silicon. We find that the barrier from (0 0 1) to (1 1 0) is approximately 0.

Investigating individual arsenic dopant atoms in silicon using low-temperature scanning tunnelling microscopy.

We study subsurface arsenic dopants in a hydrogen-terminated Si(001) sample at 77 K, using scanning tunnelling microscopy and spectroscopy. We observe a number of different dopant-related features that fall into two classes, which we call As1 and As2. When imaged in occupied states, the As1 features appear as anisotropic protrusions superimposed on the silicon surface topography and have maximum intensities lying along particular crystallographic orientations.

Site-dependent ambipolar charge states induced by group V atoms in a silicon surface.

We report that solitary bismuth and antimony atoms, incorporated at Si(111) surfaces, induce either positive or negative charge states depending on the site of the surface reconstruction in which they are located. This is in stark contrast to the hydrogenic donors formed by group V atoms in silicon bulk crystal and therefore has strong implications for the design and fabrication of future highly scaled electronic devices. Using scanning tunnelling microscopy (STM) and density functional theory (DFT) we determine the reconstructions formed by different group V atoms in the Si(111)2 × 1 surface.