Effect of fluorine and niobium co-doping on boosting the NIR blocking performance of TiO2 nanoparticles for energy efficient window

作者：Gao, Qiang; Wu, Xiaomei^*; Wang, Dongming

来源：Solar Energy, 2022, 238: 60-68.

DOI：10.1016/j.solener.2022.04.023

• Energy efficient building
• Energy-saving window
• Titania oxide
• Co-doping
• NIR shielding
• Localized surface plasmon resonance (LSPR)

Development of novel solar shielding materials is significantly important for energy efficient windows. In this work, F-Nb codoped TiO2 (NFTO) nanoparticles with enhanced infrared radiation blocking property were synthesized for energy efficient windows. The results indicated that the co-doping of F and Nb promoted the formation of spindle-like anatase TiO2 nanocrystals. XRD, Raman and XPS studies revealed that Nb and F were successfully codoped into TiO2. The co-doping of F and Nb generated more free electrons in TiO2 crystals, which was confirmed by the bandgap widening phenomenon. The electron concentration of F-Nb doped TiO2 was as high as 3.5 x 10(20) cm(-3). Due to the enhanced plasmon resonance, the infrared blocking property of the films was vastly boosted by co-doping with niobium and fluorine. The NIR blockage efficiency of the NFTO films with a thickness of 176 mu m reached 68.5%. Furthermore, the visible transparency of NFTO films was higher than 76%. In the thermal tests, the NFTO films reduced the indoor temperature by 8.8celcius. Our results show that the F-Nb doped TiO2 nanocrystals are promising for energy efficient windows applications.