Terbium-Doped VO2 Thin Films: Reduced Phase Transition Temperature and Largely Enhanced Luminous Transmittance

• Main Authors: Wang, Ning, Duchamp, Martial, Dunin-Borkowski, Rafal E., Liu, Shiyu, Zeng, Xianting, Cao, Xun, Long, Yi
• Other Authors: School of Materials Science & Engineering
• Format: Article
• Language: English
• Published: 2016
• Subjects: Vanadium dioxide; Terbium-doping; Thermochromic properties; Sol-gel; Smart windows
• Online Access: https://hdl.handle.net/10356/84947; http://hdl.handle.net/10220/40490
• Institution: Nanyang Technological University

Vanadium dioxide (VO2) is a well-known thermochromic material with large IR modulating ability, promising for energy-saving smart windows. The main drawbacks of VO2 are its high phase transition temperature (τc = 68 °C), low luminous transmission (Tlum), and weak solar modulating ability (ΔTsol). In this paper, the terbium cation (Tb3+) doping was first reported to reduce τc and increase Tlum of VO2 thin films. Compared with pristine VO2, 2 at. % doping level gives both enhanced Tlum and ΔTsol from 45.8% to 54.0% and 7.7% to 8.3%, respectively. The Tlum increases with continuous Tb3+ doping and reaches 79.4% at 6 at. % doping level, representing ∼73.4% relative increment compared with pure VO2. This has surpassed the best reported doped VO2 thin films. The enhanced thermochromic properties is meaningful for smart window applications of VO2 materials.