Preparation and thermochromic properties of B-Mg co-doped nano-VO2
LÜWeizhong1,ZHOU Qiaoting1,2,ZHOU Tianzi1,HUANG Chunbo1,LI Liangpu1,HUA Yue1,ZHOU Shaohua1

1.College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518071, Guangdong Province, P. R. China;2.Guangzhou Institute of Quality Supervision and Inspection, Guangzhou 511400, Guangdong Province, P. R. China

smart materials; vanadium dioxide (VO2); sol-gel-assisted hydrothermal method; B-Mg co-doping;thermochromic properties; phase transition temperature

DOI: 10.3724/SP.J.1249.2022.04440


In order to reduce the phase transition temperature of vanadium dioxide (VO2) materials and improve the optical properties of VO2 materials, the boron-magnesium (B-Mg) co-doped vanadium dioxide (VO2) powders were prepared through a sol-gel-assisted hydrothermal method in combination with the subsequent high-temperature annealing. The obtained powder was further prepared into a thin film. X-ray diffraction (XRD), X-ray electron spectroscopy (XPS), field emission scanning electron microscope (FESEM), differential scanning calorimeter (DSC), ultraviolet-visible-near-infrared spectrophotometer (UV-vis-NIR) were used to explore the microstructure of the material and effects of the doping concentrations of Mg on the phase transition temperature tc and the optical properties of VO2 materials. The B-Mg co-doped nano-VO2 material that satisfies various application standards was obtained. The results show that the doped elements of B and Mg exist in the VO2 structure as the form of B3+ and Mg2+. When the atomic percentages of B and Mg are 6. 0% and 1. 8%, the material shows a relatively excellent thermochromic properties, with the lowest phase transition temperature tc = 30. 8 ℃. The sunlight modulation amplitude ΔTsol of the material is 11. 8%, which is maintained above 10%. The average visible light transmittance Tlum of the material is 69. 7%, which is 12. 1% higher than that of the undoped VO2 film. The properties above meet the requirements for the application in thermochromic smart windows. This work provides scientific basis for the preparation of VO2 materials suitable for thermochromic smart windows.