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Shiping Huang

Publications and source records attributed to Shiping Huang.

3 recordsLinked to original sources

The onion-ring structure for Pd-Pt bimetallic clusters.

The onion-ring structure is validated in the Pd-Pt bimetallic clusters of total atom numbers 147 and 309 through the Monte Carlo method by using the second-moment approximation of the tight-binding (TB-SMA) potentials, which is conceived in predicting the possible structures of the bimetallic clusters by He et al. [J. Am. Chem. Soc. 2003, 125, 11034] and Hwang et al. [J. Am. Chem. Soc. 2005, 127, 11140]. In the onion-ring structure, Pd atoms and Pt atoms occupy alternate layers of the clusters. The formation of the onion-ring structure can be associated with the fact that the single Pt impurity is favorable to stay in the subsurface layer and the central part of bimetallic clusters.

Letter↗

Role of the catalyst in the growth of single-wall carbon nanotubes.

Classical molecular dynamics simulations are carried out to analyze the physical state of the catalyst, and the growth of single-wall carbon nanotubes under typical temperature and pressure conditions of their experimental synthesis, emphasizing the role of the catalyst/substrate interactions. It is found that a strong cluster/substrate interaction increases the cluster melting point, modifying the initial stages of carbon dissolution and precipitation on the cluster surface. Experiments performed on model Co-Mo catalysts clearly illustrate the existence of an initial period where the catalyst is formed and no nanotube growth is observed. To quantify the nature of the Co-Mo2C interaction, quantum density functional theory is applied to characterize structural and energetic features of small Co clusters deposited on a (001) Mo2C surface, revealing a strong attachment of Co-clusters to the Mo2C surface, which may increase the melting point of the cluster and prevent cluster sintering.

Catalysis↗

Molecular dynamics simulation of room-temperature ionic liquid mixture of [bmim][BF4] and acetonitrile by a refined force field.

1-Butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]) is one of the promising room-temperature ionic liquids. To test the refined force field for [bmim][BF4] proposed in our previously work (J. Phys. Chem. B, 2004, 108, 12978-12989), thermodynamic properties of mixtures of [bmim][BF4](1)+ acetonitrile (2) are presented by using molecular dynamics over the whole concentration range. The calculated densities are in good agreement with the experimental data with deviations less than 2%, indicating the force field is applicable to the mixtures. In addition, the diffusion constants, viscosities, heats of vaporization, cohesive energy densities and excess properties of the mixtures are reported. The microscopic structures are discussed in detail, corresponding to the thermodynamic properties.

Acetonitriles↗