基于尺寸效应及温度效应的纳米ZnS热力学性质研究

Investigation on thermodynamic properties of nano-sized ZnS based on particle size effect and temperature effect

材料粒度达到纳米级别时会产生特殊的表面效应及小尺寸效应,因此纳米材料往往表现出不同于本体材料的独特性质.该文着重在尺寸效应及温度效应上对ZnS纳米材料的热力学性质展开研究,探究了一种水热法制备出5种不同尺寸的纳米ZnS,并在不同温度下测定其在水溶液中平衡时的电导率.根据所得数据,以热力学循环法、溶解热力学理论以及电化学热力学平衡原理为基础,探讨了颗粒粒度和温度与纳米ZnS热力学性质之间的规律.结果表明:纳米ZnS的溶解热力学函数、摩尔表面热力学函数、偏摩尔表面热力学函数和规定热力学函数均与粒径、温度均具有良好的线性关系.该文进一步完善了溶解热力学理论,为涉及相关纳米材料的研究提供了理论支撑.

Nanomaterials often exhibit unique properties that are different from those of their parent material because of the special surface and small size effects that occur when the material reaches the nanometer level.This work focuses on the size effect and temperature effect on the thermodynamic properties of ZnS nanomaterials.In this paper,a hydrothermal method was investigated to prepare five different sizes of ZnS nanoparticles and to determine their electrical conductivity at different temperatures in equilibrium in aqueous solution.According to the obtained data,based on the thermodynamic cycle method,the theory of dissolution thermodynamics and the principle of electrochemical thermodynamic equilibrium,the law between particle size and temperature and the thermodynamic properties of nano-ZnS was discussed.The result shows that the dissolution thermodynamic function,molar surface thermodynamic function,partial molar surface thermodynamic function and prescribed thermodynamic function of nano-ZnS all have a good linear relationship with particle size and temperature.The dissolution thermodynamic function,molar surface thermodynamic function,partial molar surface thermodynamic function and prescribed thermodynamic function of nano-ZnS all have a good linear relationship with particle size and temperature.This paper further demonstrated the theory of dissolution thermodynamics and provides theoretical support for studies involving related nanomaterials.