空位缺陷
氧气
转化(遗传学)
纳米颗粒
相(物质)
材料科学
化学物理
化学工程
化学
纳米技术
结晶学
有机化学
工程类
生物化学
基因
作者
Chandana Rath,P. Mohanty,Avinash C. Pandey,N. C. Mishra
标识
DOI:10.1088/0022-3727/42/20/205101
摘要
Nanosize TiO2 powders prepared by the sol–gel technique at pH of precipitation 4.5 and 6.5 show the anatase phase after calcining at 500 °C. Anatase to rutile phase transformation (ART), however, occurs at 650 °C in the case of pH 6.5 while 850 °C is found to be the ART temperature for the lower pH sample. pH of precipitation dependent ART temperature has not been reported so far to the best of our knowledge. It is known that the smaller the particle size, the lower the ART temperature, and vice versa. The observation of higher crystallite size and lower ART temperature in the case of the higher pH sample contradicts the reported result. We realized from x-ray photoelectron spectroscopic studies that oxygen vacancy concentration drives the ART temperature to lower values in the higher pH sample compared with the sample synthesized at lower pH; even the particle size is found to be higher in the former one.
科研通智能强力驱动
Strongly Powered by AbleSci AI