研究目的
Investigating the effects of different alkali species (NH4HCO3, NH3·H2O, NaOH) on the formation and crystallinity of vanadium dioxide (VO2) and its tungsten doping for thermochromic applications.
研究成果
NaOH accelerates VO2 crystal formation and improves crystallinity but hinders tungsten doping due to quick frame formation. NH4HCO3 allows slower crystal formation, facilitating tungsten doping and reducing transition temperature, though with lower crystallinity and latent heat. Vacuum drying improves VO2 formation ratio, especially for NH4HCO3. Further investigation is needed to confirm doping mechanisms.
研究不足
The study notes that tungsten doping did not complete with a bimodal endothermic peak, indicating incomplete doping; further experiments are needed to improve doping concentration and prove assumptions about crystal frame formation.
1：Experimental Design and Method Selection:
The study investigates the effects of alkali species on VO2 formation and tungsten doping using a precipitation method with VOSO4 as the vanadium source, followed by calcination under N2 atmosphere.
2：Sample Selection and Data Sources:
Samples were prepared by adding alkali solutions (NH4HCO3, NH3·H2O, NaOH) to VOSO4 aqueous solutions, with/without tungsten doping using Na2WO4·2H2O.
3：2O. List of Experimental Equipment and Materials:
3. List of Experimental Equipment and Materials: Materials include VOSO4·nH2O, NH4HCO3, NH3·H2O, NaOH, Na2WO4·2H2O, distilled water, ethanol, acetone; equipment includes centrifuge, FE-SEM (SM-7600F, JEOL), dynamic light scattering (Microtrac MT3200II), XRD (MiniFlex600, Rigaku), TG/DTA (TG-8102, Rigaku), DSC (Thermo Pluss DSC8230, Rigaku).
4：Experimental Procedures and Operational Workflow:
Alkali solutions were dropped into VOSO4 solutions, stirred, centrifuged, rinsed, dried at 60°C (air or vacuum), and calcined at 600°C under N
5：For tungsten doping, Na2WO4 solution was mixed before alkali addition. Characterizations included SEM, particle size analysis, XRD, TG/DTA, and DSC. Data Analysis Methods:
XRD patterns analyzed for FWHM and crystalline size using Scherrer's equation; DSC for transition temperature and heat storage; TG/DTA for weight loss and crystallization temperatures.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容-
Field Emission Scanning Electron Microscope
SM-7600F
JEOL
Observing the morphology of powder samples
暂无现货
预约到货通知
-
X-ray Powder Diffraction
MiniFlex600
Rigaku
Measuring crystal structures of samples
立即获取同款设备
-
Thermogravimetric Analysis
TG-8102
Rigaku
Analyzing weight loss and thermal events during heating
暂无现货
预约到货通知
-
Differential Scanning Calorimetry
DSC8230
Rigaku
Investigating transition temperature and heat storage capacity
暂无现货
预约到货通知
-
Dynamic Light Scattering
MT3200II
Microtrac BEL
Measuring size distributions of powders dispersed in distilled water
暂无现货
预约到货通知
-
Osmium Coater
OPC60A
Filgen
Coating samples for SEM observation
暂无现货
预约到货通知
-
登录查看剩余4件设备及参数对照表
查看全部
