水热合成Cs_(0.32)WO_3纳米粒子的结构特点及其近红外吸收特性

Near-infrared Absorption Properties and Structural Characteristics of Hydrothermally Synthesized Cs_(0.32)WO_3 Nanoparticles

以钨酸钠和碳酸铯为原料,以D-苹果酸为还原剂,采用水热法成功合成了棒状Cs_(0.32)WO_3纳米粒子,并通过共混法将其与SiO2溶胶混合,在玻璃基板上制备了透明隔热涂层.采用X射线衍射(XRD)、扫描电镜(SEM)及紫外-可见-近红外漫反射吸收光谱对其进行表征,考察了粉体结晶度和微观形貌等结构特点对其近红外吸收性能的影响.结果表明:在水热合成过程中,原料的Cs/W比(摩尔比)为0.5时,可促进六方晶型Cs_(0.32)WO_3纳米粒子的生成;随着反应时间的增加,Cs_(0.32)WO_3纳米粒子形貌由不规则形状逐渐变成棒状;所得Cs_(0.32)WO_3纳米粒子的近红外吸收能力,随结晶度提高而提高,并且随纳米棒状形貌的形成而大幅提高.利用该纳米粒子制备的隔热玻璃保持了较高的可见光透过率,为71.6%,而近红外光透过率仅为10.2%,展现出优异的近红外屏蔽性能,表明Cs_(0.32)WO_3纳米材料在汽车车窗玻璃及建筑玻璃领域具有良好的应用前景.

Cs0.32WO3 rod-like nanoparticles were successfully synthesized via a hydrothermal method using sodium tungstate and cesium carbonate as raw materials and D-malic acid as reducing agents.Additionally,transparent near-infrared(NIR)shielding film was prepared by coating the mixture of dispersed solution of Cs0.32WO3 nanoparticle with SiO 2 sol on glass substrate.The effects of crystallinity and microstructure on NIR absorption properties of Cs0.32WO3 nanoparticles were characterized by X-ray diffraction(XRD),scanning electron microscope(SEM)and UV-Vis-NIR spectroscopy.The results show that the sample with n(Cs)/n(W)=0.5 promotes the formation of hexagonal Cs0.32WO3 during hydrothermal synthesis.Moreover,with increasing reaction time,the morphology of the sample changes from irregular-shaped nanoparticles to rod-like nanoparticles.The NIR absorption ability of the prepared Cs0.32WO3 nanoparticles increases with increasing crystallinity.Moreover,this absorption ability increases greatly when the rod-like morphology nanoparticles form.The visible light transmittance of the prepared insulated glass with Cs0.32WO3 transparent coating is kept at 71.6%,while the transmittance of NIR light is only 10.2%.It reveals excellent optical transmissionand NIR absorption properties,showing application potentials in the fields of automobile window glass and building glass.