物理化学学报 >> 2005, Vol. 21 >> Issue (04): 446-449.doi: 10.3866/PKU.WHXB20050421

研究简报 上一篇    下一篇

纳米氧化锌的低温热容和热力学性质

岳丹婷; 谭志诚; 董丽娜; 孙立贤; 张涛   

  1. 中国科学院大连化学物理研究所热化学实验室, 大连 116023; 大连海事大学轮机学院, 大连 116026
  • 收稿日期:2004-09-29 修回日期:2004-11-23 发布日期:2005-04-15
  • 通讯作者: 谭志诚 E-mail:tzc@dicp.ac.cn

Low-temperature Heat Capacity and Thermodynamic Functions of Nano ZnO

YUE Dan-Ting; TAN Zhi-Cheng; DONG Li-Na; SUN Li-Xian; ZHANG Tao   

  1. Thermochemistry Laboratory. Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023; Marine Engineering College, Dialian Maritime University, Dalian 116026
  • Received:2004-09-29 Revised:2004-11-23 Published:2005-04-15
  • Contact: TAN Zhi-Cheng E-mail:tzc@dicp.ac.cn

摘要: 用扫描电子显微镜(SEM)测定了纳米氧化锌试样的粒径, SEM结果表明ZnO试样平均粒径为30 nm. 在83~350 K温区, 用精密低温绝热量热计测定了ZnO的等压摩尔热容, 拟合出其等压摩尔热容与热力学温度的函数关系式: Cp=-3.249+0.2400T-3.413×10-4T 2+4.485×10-7T 3. 根据热容与热力学函数关系, 计算了以298.15 K为基准的纳米ZnO的热力学函数, 并与粗晶ZnO和18 nm ZnO热容文献报导值进行了比较, 从能量角度分析了不同粒径ZnO热容曲线差别产生的原因.

关键词: 纳米氧化锌, 低温热容, 热力学函数

Abstract: The size of nano ZnO powders was determined to be 30 nm in diameter by SEM. The isobaric molar heat capacity Cp of the nano ZnO was measured with high precision adiabatic low-temperature calorimeter in temperature range from 83 K to 350 K. The relationship of Cp with temperature T was established as: Cp=-3.249+0.2400T-3.413×10-4T 2+4.485×10-7T 3. The thermodynamic functions of the nano ZnO, relative to the standard temperature of 298.15 K, were derived based on the heat capacity data through thermodynamic relationship. The measured Cp values were compared with those of coarse crystal and 18 nm ZnO powders cited from literature and the difference between the Cp curves was analyzed.

Key words: Nano ZnO, Low-temperature heat capacity, Thermodynamic functions