Time filter

Source Type

Li S.,Zhejiang University | Wang M.,Zhejiang University | Luo Y.,Zhejiang University | Luo Y.,Shaoxing Test Institute of Quality and Technical Supervision | Huang J.,Zhejiang University
ACS Applied Materials and Interfaces | Year: 2016

A bioinspired hierarchical nanofibrous Fe3O4-TiO2-carbon composite was fabricated by employing natural cellulose substance (e.g., filter paper) as both the scaffold and the carbon source and showed improved electrochemical performances when it is employed as an anode material for lithium-ion batteries. FeOOH nanoparticles were first grown uniformly onto the surface of the titania thin-layer precoated cellulose nanofibers, and thereafter, the as-prepared FeOOH-TiO2-cellulose composite was calcined and carbonized in argon atmosphere at 500 °C for 6 h to produce the Fe3O4-TiO2-carbon composite. The resultant composite possesses a hierarchical structure that was faithfully inherited from the initial cellulose substance, which was composed of titania-coated carbon fibers with corncob-like shaped Fe3O4 nanoparticles immobilized on the surfaces. The diameter of the composite nanofiber is ca. 100-200 nm, and the diameter of the Fe3O4 nanoparticle is about 30 nm, which is coated with an ultrathin carbon layer with a thickness about 3 nm. This composite displayed superior lithium-ion storage performance. It showed a first-cycle discharge capacity of 1340 mAh/g, delivering a stable reversible capacity of ca. 525 mAh/g after 100 charge-discharge cycles at a current density of 100 mA/g, and the efficiency is as high as ca. 95% of the theoretical value. This is much higher than those of the commercial Fe3O4 powder (160 mAh/g) and the Fe3O4-carbon counter material (310 mAh/g). It was demonstrated that the thin titania precoating layer (thickness ca. 3-5 nm) is necessary for the high content loading of the Fe3O4 nanoparticles onto the carbon nanofibers. Owing to the unique three-dimensional porous network structure of the carbon-fiber scaffold, together with the ultrathin outer carbon-coating layer, the composite showed significantly improved cycling stability and rate capability. © 2016 American Chemical Society.

Li S.-C.,Shaoxing Test Institute of Quality and Technical Supervision | Hu S.-J.,Shaoxing Test Institute of Quality and Technical Supervision | Du N.,Zhejiang University | Fan J.-N.,Shaoxing Test Institute of Quality and Technical Supervision | And 2 more authors.
Rare Metals | Year: 2015

A novel and simple chemical reaction method was developed to synthesize dendrite-like La(OH)3 nanostructures which was composed of centripetal arranged La(OH)3 nanorods with diameters of 50–100 nm and lengths of several micrometers. The effect of different alkaline sources on the morphology of La(OH)3 nanostructures was investigated. It is indicated that diethylenetriamine acts not only as an alkaline source, but also as a surfactant which induces the centripetal growth of La(OH)3 nanostructures. Moreover, dendrite-like La2O3 nanostructures were prepared by the calcination of La(OH)3 nanostructures at 750 °C. The morphology, structure, and composition of the as-synthesized products were characterized by transmission electron microscopy (SEM), high-resolution transmission electron microscopy, field emission scanning electron microscopy (FESEM), and X-ray powder diffraction (XRD). © 2013, The Nonferrous Metals Society of China and Springer-Verlag Berlin Heidelberg.

Hu S.,Shaoxing Test Institute of Quality and Technical Supervision | Xu J.,Shaoxing Test Institute of Quality and Technical Supervision | Huang X.,Nanjing University of Aeronautics and Astronautics | Li S.,Shaoxing Test Institute of Quality and Technical Supervision
Bandaoti Guangdian/Semiconductor Optoelectronics | Year: 2012

Si-C-H thin films were prepared by using plasma-enhanced chemical vapor deposition (PECVD) method under different processing parameters, with the gas mixture of CH 4 and SiH 4. The influence of the processing parameters, such as CH 4/SiH 4 and radio-frequency power density, on the structure and properties of the films were analyzed. The results suggested that the films were composed of amorphous SiC, in which Si crystalline grains inlayed, and hydrogen atoms were in a C-H configuration. Higher radio-frequency power density and CH 4/SiH 4 value would accelerate the formation of Si-C configuration, but lower CH 4/SiH 4 value would accelerate the crystallization of the films. The electrical resistivity of the films increases with the increase of CH 4/SiH 4 value, but decreases with the increase of the radio-frequency power density.

Discover hidden collaborations