Thin, rectangular C60 nanorods in face‐centered cubic structure are synthesized by using m‐xylene as a shape controller. These unusual nanorods (see figure) can easily grow on various substrates. The smallest nanorods have widths smaller than 30 nm. The nanorods are highly crystalline in single phase. A significant expansion of the lattice constant is also found in the C60 nanorods when their widths decrease below about 80 nm.

Single-crystalline C 60 ‚1m-xylene nanorods with a hexagonal structure were successfully synthesized by evaporating a C 60 solution in m-xylene at room temperature. The ratio of the length to the diameter of the nanorods can be controlled in the range of ≈10 to over 1000 for different applications. The photoluminescence (PL) intensity of the nanorods is about 2 orders of magnitude higher than that for pristine C 60 crystals in air. Both UV and Raman results indicate that there is no charge transfer between C 60 and m-xylene. It was found that the interaction between C 60 and m-xylene molecules is of the van der Waals type. This interaction reduces the icosahedral symmetry of C 60 molecule and induces strong PL from the solvate nanorods.

In this paper, CeO 2 nanocubes with the (200)terminated surface/graphene sheet composites have been prepared successfully by a simple hydrothermal method. It is found that the CeO 2 nanocubes with high crystallinity and specific exposed surface are well dispersed on well-exfoliated graphene surface. The (200)-terminated surface/graphene sheet composites modified electrode showed much higher sensitivity and excellent selectivity in its catalytic performance compared to a CeO 2 nanoparticle-modified electrode. The photoluminescence intensity of the CeO 2 anchored on graphene is about 30 times higher than that of pristine CeO 2 crystals in air. The higher oxygen vacancy concentration in CeO 2 is supposed to be an important cause for the higher photoluminescence and better electrochemical catalytic performance observed in the (200)-terminated surface/graphene sheet composites. Such ingenious design of supported well-dispersed catalysts in nanostructured ceria catalysts, synthesized in one step with an exposed high-activity surface, is important for technical applications and theoretical investigations.

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Raman spectra of single-walled carbon nanotubes ͑SWNTs͒ with diameters of 0.6-1.3 nm have been studied under high pressure. A "plateau" in the pressure dependence of the G-band frequencies was observed in all experiments, both with and without pressure transmission medium. Near the onset of the G-band plateau, the corresponding radial breathing mode ͑RBM͒ lines become very weak. A strong broadening of the full width at half maximum of the RBMs just before the onset of the G-band plateau suggests that a structural transition starts in the SWNTs. Raman spectra from SWNTs released from different pressures also indicate that a significant structural transition occurs during the G-band plateau process. Simulations of the structural changes and the corresponding Raman modes of a nanotube under compression show a behavior similar to the experimental observations. Based on the experimental results and the theoretical simulation, a detailed model is suggested for the structural transition of SWNTs, corresponding to the experimentally obtained Raman results in the high-pressure domain.

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With ever increasing interest in layered materials, molybdenum disulfide has been widely investigated due to its unique optoelectronic properties. Pressure is an effective technique to tune the lattice and electronic structure of materials such that high pressure studies can disclose new structural and optical phenomena. In this study, taking MoS2 as an example, we investigate the pressure confinement effect on monolayer MoS2 by in situ high pressure Raman and photoluminescence (PL) measurements. Our results reveal a structural deformation of monolayer MoS2 starting from 0.84 GPa, which is evidenced by the splitting of E(1)2g and A1g modes. A further compression leads to a transition from the 1H-MoS2 phase to a novel structure evidenced by the appearance of two new peaks located at 200 and 240 cm(-1). This is a distinct feature of monolayer MoS2 compared with bulk MoS2. The new structure is supposed to have a distorted unit with the S atoms slided within a single layer like that of metastable 1T'-MoS2. However, unlike the non-photoluminescent 1T'-MoS2 structure, our monolayer shows a remarkable PL peak and a pressure-induced blue shift up to 13.1 GPa. This pressure-dependent behavior might enable the development of novel devices with multiple phenomena involving the strong coupling of the mechanical, electrical and optical properties of layered nanomaterials.