Ti0.33WO3电子结构和太阳辐射屏蔽性能第一性原理研究

First-principles investigation on electronic structure and solar radiation shielding performance of Ti0.33WO3

节能减排已成为当今社会发展的主题,对节约能源、提高太阳能的高效综合利用的新型窗用透明隔热材料的理论设计和研究尤其重要.本文采用基于密度泛函理论的计算方法,研究了六方相三氧化钨Ti掺杂前、后的晶格参数、电子能带结构、形成能和光学性质.研究结果表明,Ti掺杂后晶格体积增大,系统能量降为负值,体系具有更好的稳定性;掺杂后电子能带结构发生很大的变化,但材料仍保持n型电导率;随之,其光学性质也发生改变,掺杂前h-WO3无近红外吸收性能,掺杂后的Ti0.33WO3具有很强的近红外吸收性能.在此基础上研究了Ti掺杂h-WO3前、后的太阳辐射屏蔽性能,掺杂前无太阳辐射屏蔽性能;掺杂后的Ti0.33WO3薄膜具有可见光高透明、近红外屏蔽的性能.计算结果为Ti掺杂h-WO3在窗用透明隔热材料方面的研究提供了理论依据.

With energy-saving and emission-reduction have become the theme of today's social development,the theoretical design and research of novel transparent heat insulation materials for windows,which can save energy and improve the comprehensive utilization efficiency of solar energy,are particularly crucial.In this paper,a calculation method based on DFT(density functional theory)is used to study the lattice parameters(the geometric structure of h-WO3 crystal was optimized by calculation)electronic band structure,formation energy,and optical properties of pure hexagonal phase tungsten trioxide(h-WO3)before and after doping with Ti.The calculated results indicate that the lattice volume increases and the total system energy decreases to a negative value after Ti-doped h-WO3,while the system has better stability;The electron band structure changes greatly after doping,but the material still maintains n-type conductivity.In the meantime,the optical properties of the material also changed,h-WO3 had no near-infrared absorption performance before Ti-doping,and Ti0.33WO3 after Ti-doped had strong near-infrared absorption performance.On this basis,the solar radiation shielding performance of h-WO3 before and after Ti doping has been studied.The results show that pure h-WO3 has no solar radiation shielding performance,while Ti0.33WO3 thin films after Ti-doped h-WO3 have high transparency in visible light region and strong absorption in near infrared radiation.The calculation results provide a theoretical basis for the application of transparent thermal insulating material for windows of Ti-doped h-WO3.