Showing papers by "Yong Wang published in 2009"
TL;DR: Li et al. as discussed by the authors reported that highly disordered graphene nanosheets can find promising applications in high-capacity Li ion batteries because of their exceptionally high reversible capacities and good cyclic stability.
Abstract: Graphene has aroused intensive interest because of its unique structure, superior properties, and various promising applications. Graphene nanostructures with significant disorder and defects have been considered to be poor materials because disorder and defects lower their electrical conductivity. In this paper, we report that highly disordered graphene nanosheets can find promising applications in high-capacity Li ion batteries because of their exceptionally high reversible capacities (794−1054 mA h/g) and good cyclic stability. To understand the Li storage mechanism of graphene nanosheets, we have prepared graphene nanosheets with structural parameters tunable via different reduction methods including hydrazine reduction, low-temperature pyrolysis, and electron beam irradiation. The effects of these parameters on Li storage properties were investigated systematically. A key structural parameter, Raman intensity ratio of D bands to G bands, has been identified to evaluate the reversible capacity. The gr...
944 citations
TL;DR: In this article, a facile templated chemical vapor deposition (CVD) method was used to produce CNT-encapsulated Sn nanoparticles with ∼100% particle encapsulation and high filling uniformity.
Abstract: In this study we demonstrate a facile templated chemical vapor deposition (CVD) method to produce CNT-encapsulated Sn nanoparticles with ∼100% particle encapsulation and high filling uniformity. The encapsulated Sn particles were formed either as Sn or Sn@carbon core−shell particles with good control of size and morphology. The complete and uniform encapsulation of small, electrochemically active Sn particles within a CNT matrix with large free volume accommodated the volume excursion problem in repetitive lithium insertion and extraction reactions very well, showing good resilience in maintaining electrical connective and mechanical integrity. Consequently the completely filled Sn@CNT nanocomposite showed excellent reversible lithium ion storage properties.
194 citations
TL;DR: The fully tubular nanostructure was found to be the most suitable for reversible Li(+) storage and out of an initially large capacity, 654 mA h g(-1) could still be retained after 40 cycles of charge and discharge.
Abstract: This paper presents a facile method of preparation whereby one-dimensional SnO2 nanostructures of different morphologies, namely nanotubes, nanotube?nanorod hybrids and nanorods, could be obtained by thermally treating an alumina template loaded with SnCl4 aqueous solution in air. The fraction of interior cavity could be tuned by varying the precursor concentration in the preparation. The fully tubular nanostructure was found to be the most suitable for reversible Li+ storage. Out of an initially large capacity of 976?mA?h?g?1, 654?mA?h?g?1 could still be retained after 40 cycles of charge and discharge.
35 citations
TL;DR: In this paper, a facile solution route (water bath heating or hydrothermal heating) was reported for synthesizing a few Sb-based self-assembly structures including bundles of nanowires, nanowire-flowers, long-nodes, bundles of flakes, nanobelts, hollow prisms.
14 citations
06 Jul 2009
TL;DR: In this article, a new junction depth measurement technique for textured silicon solar cells is investigated, and both experience and experimental data indicate that the measurement technique used is feasible and accurate.
Abstract: It's difficult to measure junction depth because the junction is not in horizontal direction in textured silicon solar cells. In this paper a new, accurate junction depth measurement technique for textured silicon solar cells is investigated. Both experience and experimental data indicate that the measurement technique we used is feasible.
4 citations
06 Jul 2009
TL;DR: In this article, the authors found that during the cooling, the electrical characteristics and internal or external quantum efficiency nearly stayed the same, and the lifetime of minority carriers as well, and that cooling was a available way to apply in industrial process.
Abstract: Cooling was a very effective way to eliminate the bow of Silicon solar cell. In this paper, by a series of experiments, we found that during the cooling, the electrical characteristics and internal or external quantum efficiency nearly stayed the same, and the lifetime of minority carriers as well. The cooling was a available way to apply in industrial process.
3 citations