尺寸效应对氧化锌微/纳体系热力学性质的影响  

Impact of Size Effects on the Thermodynamic Properties of Zinc Oxide Micro/nano System

作　　者：范高超[1] 黄在银[1,2] 陈洁[1] 马玉洁[1] 

机构地区：[1]广西民族大学化学与生态工程学院,南宁530006 [2]广西壮族自治区林产化学品开发与应用重点实验室,南宁530006

出　　处：《化学学报》2012年第7期938-942,共5页Acta Chimica Sinica

基　　金：国家自然科学基金(No.20963001);广西自然科学基金(Nos.0832078;0991085);广西区研究生科研创新项目(No.2011106080817M366)资助~~

摘　　要：采用微乳液水热辅助法合成了三种不同尺寸的手榴弹状ZnO微/纳结构.通过设计热化学循环,建立了纳米ZnO与块体ZnO体系热力学性质之间的关系.并结合微量热技术对不同尺寸ZnO微/纳体系的热力学性质进行了计算.结果表明,尺寸效应对微/纳体系热力学性质有显著的影响:随着反应物尺度的减小,体系的标准摩尔反应焓、标准摩尔反应Gibbs自由能、标准摩尔反应熵均降低,而材料自身的标准摩尔生成焓、标准摩尔生成Gibbs自由能、标准摩尔熵均增加.Grenade-like ZnO micro/nano structures with three different sizes were prepared by microemul- sion-mediated hydrothermal route. Through designing a thermochemical cycle, the relationship between thermodynamic properties of nano ZnO and bulk ZnO systems was built. Combined with microcalorimetry, thermodynamic properties of the ZnO micro/nano systems with different sizes were calculated. The results revealed that size effect has significant influences on thermodynamic properties of micro/nano systems. Along with the size of reactants decreasing, the standard molar enthalpy of reaction, standard molar Gibbs free energy of reaction and standard molar entropy of reaction of micro/nano systems decreased, but the standard molar enthalpy of formation, standard molar Gibbs free energy of formation and standard molar en- tropy of themselves increased.

关 键 词：热力学性质 微量热技术 纳米ZNO 尺寸效应:微乳液法 

分 类 号：O614.241[理学—无机化学]