In this paper, we reported a Raman scattering study of epitaxial graphene on different doped 6H-SiC ͑0001͒ substrates and investigated the substrate induced charge-transfer doping to the epitaxial graphene. We found that the charge carrier type and concentration of epitaxial graphene can be altered by SiC substrates with different doping level and doping type. This effect is comparable to that obtained by electrochemical doping. As Raman scattering is very sensitive to the doping level, the charge carrier concentration of epitaxial graphene can be estimated by the Raman G-peak shift. Our results are fundamental and may have implications for future epitaxial-graphene-based micro/ nanoelectronic devices.

An approach to fabricate large‐scale graphene nanoribbons (GNRs) with tunable ribbon widths is presented. Regular steps with variable heights from 1 to 100 nm can be prepared on a SiC substrate by a low‐pressure etching process. Graphene can be epitaxially grown only on the side walls of the steps, thereby leading to GNRs with controllable widths.

Spherical organic-bonded ZnS nanocrystals with 4.0±0.2 nm in diameter are synthesized by a liquid-solid-solution method. The photoluminescence spectrum of sample ([S 2− ]/[Zn 2+ ] = 1.0) shows a strong white emission with a peak at 490 nm and ∼ 170 nm full widths at half maximum. By Gauss fitting, the white emission is attributed to the overlap of a blue emission and a green-yellow emission, originating from electronic transitions from internal S 2− vacancies level to valence band and to the internal Zn 2+ vacancy level, respectively. After sealingZnS nanocrystals onto InGaN chips, the device shows CIE coordinates of (0.29,0.30), which indicates their potential applications for white light emitting diodes.