http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Facile synthesis of tin oxide nanofibres
안중호,왕과시우,Yong-Jin Kim 한국물리학회 2009 Current Applied Physics Vol.9 No.2
In this paper, we present a facile method to synthesize SnO2 nanofibres. Unlike the conventional CVD process for synthesizing nanofibres, the present synthesis method needs neither specific source gas nor substrates. Sn–Ag alloys or powder mixtures were heat-treated at temperatures above their melting point in a vertical or horizontal alumina tube furnace. During the heat treatment, a small amount of oxygen in an atmospheric gas reacted with tin in the alloys to form SnO2 nanofibres. Silver in the tin alloys acts as a catalytic material to facilitate the formation of nanofibres. An excess amount of oxygen in the gas resulted in the formation of SnO2 nanoparticles instead of nanofibres. The synthesized nanofibres have straight form with high purity.
Xiao-Yu Cao,Shuangqiang Chen,왕과시우 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.4
Abandoned peanut shells, a common farm waste, have caused tremendous environmental pollution and huge waste deposits through burned and buried disposal approaches. In targeting to enhance the potential value of peanut shells and discover a new alternative candidate for lithium ion batteries, we adopted an easy to scale-up and highly repeated method to treat fresh and dry peanut shells via acid-treatment and pyrolysis, making porous structures on carbonized peanut shells. The pyrolysis process transformed the peanut shells to porous carbon (PC) materials in a quartz tube furnace at a series of temperatures from 500°C to 700°C in N2 under the condition of 40°C gradient temperatures with a heating rate of 2°C min−1. Scanning electron microscopy (SEM) images show that the irregular porous structures and hundreds of micropores are distributed on the PC materials. The cyclic voltammogram (CV) test and particle size analysis are employed to investigate their characteristics of voltammetry and particle size distribution. PC material obtained at 620°C (PC-620) exhibited good particle distribution, porous structure and less agglomerated particles. When applied as anode materials in lithium ion batteries, the PC-620 electrode displayed the high reversible capacity of 608 mAh g–1. Moreover, the cycling performance of PC-620 was the most stable, with a high Coulombic efficiency of 98.9% at the 20th cycle, demonstrating a reversible capacity of 418 mAh g–1, which is higher than the theoretical capacity of graphite. Most importantly, the PC materials harvested from the wastes of natural resources are turned into valuable electrode materials for the high demand energy storage devices, which can significantly reduce severe environmental pollution and alleviate an energy shortage.