Shuankui Li

One-pot synthesis of ZnS hollow spheres via a low-temperature, template-free hydrothermal route

ZnS hollow nanospheres with porous shells were successfully fabricated by a simple one-pot template-free hydrothermal route with the assistance of trolamine. The hollow nanospheres with a mean diameter of about 220 nm and the pore size of the porous shell of about 3.2 nm exhibit large BET surface areas of 129.9 m2 g−1. The formation of ZnS hollow nanospheres was definitely driven by the well-known Ostwald ripening process. The morphology of the product could be controlled by adjusting the volume of trolamine in the ternary solution, which could influence the nucleation density and rate of the growing region during the initial stage of reaction. As synthesized, highly defective nanocrystalline ZnS exhibits a very strong defect-related green emission, which may pertain to the emission enhancement of the unique geometrical morphology of ZnS hollow nanospheres with a porous shell. The observed green PL emission of the wurtzite-type ZnS nanomaterials could provide an interesting application in the development of novel luminescent devices.

3D flower-like hierarchitectures constructed by SnS/SnS 2 heterostructure nanosheets for high-performance anode material in lithium-ion batteries

Sn chalcogenides, including SnS, Sn2S3, and SnS2, have been extensively studied as anode materials for lithium batteries. In order to obtain one kind of high capacity, long cycle life lithium batteries anode materials, three-dimensional (3D) flowerlike hierarchitectures constructed by SnS/SnS2 heterostructure nanosheets with thickness of ∼20nm have been synthesized via a simple one-pot solvothermal method. The obtained samples exhibit excellent electrochemical performance as anode for Li-ion batteries (LIBs), which deliver a first discharge capacity of 1277 mAhg-1 and remain a reversible capacity up to 500 mAhg-1 after 50 cycles at a current of 100 mAhg-1.

High rate performance SnO2 based three-dimensional graphene composite electrode for lithium-ion battery applications

In order to improve the rate performance and cycling stability at high current densities of lithium-ion batteries (LIBs), a sample composite of SnO2 and three-dimensional graphene (SnO2/3DG) was fabricated using a hydrothermal method, with polystyrene balls (PS) as templates. The reversible capacity is 720.8 mA h g−1 at a current density of 100 mA g−1, after 100 cycles. The rate performance is also excellent, with a reversible capacity of about 800 mA h g−1 at 1000 mA g−1. The excellent electrochemical performance is attributed to its 3D structure, which possesses a large specific surface area and abundant reaction active positions, leading to fast kinetics and short pathways for both Li-ions and electrons.

EFFECT OF PD AND RH METALS ON ELECTRICAL-PROPERTIES OF THE SI-SIO2 INTERFACE

Abstract The negative electrical effects of Pd and Rh metals at the Si-SiO 2 interface and the heat treatment behavior of these effects are studied experimentally. In addition, the results of electron spectroscopy analysis of the impurity-doped interfaces are also presented.