Journal of Nanomedicine & Nanotechnology

Self-assembled spinodally decomposed VO2-based nanostructured thin films for thermochromic applications

Joint Event on 23^rd International Conference on Nanomaterials science & Nanoengineering & Technology & International Conference and Exhibition on Pharmaceutical Nanotechnology and Nanomedicine

April 18-19, 2018 | Las Vegas, USA

Xun Cao, Hongjie Luo and Ping Jin

Shanghai Institute of Ceramics, China
National Institute of Advanced Industrial Science and Technology, Japan

Accepted Abstracts: J Nanomed Nanotechnol

Abstract:

Vanadium dioxide (VO2) is a renowned oxide owing to its reversible first-order semiconductor-metal phase transition between low-temperature monoclinic (M) phase and high-temperature rutile (R) phase. For applications, the M phase is almost transparent to infrared light while the R phase is highly reflective, maintaining visible light transmittance. For this reason, VO2-based thin films provide a promising application in energy-saving smart windows. One of the most efficient ways for fabricating highperformance films is to create multi-nanolayered structure. However, it is highly complex to make such layers in the VO2-based films when using conventional techniques. Here, we report a facile two-step approach, i.e., the room temperature magnetron sputteringâ?? annealing approach, to fabricate multilayered VO2-TiO2 thin films via spinodal decomposition mechanism. The layered structure and the resulting performances of the film can be optimized just by varying the degree of annealing. We use different types of sapphire substrates (A-plane (11-20) sapphire, R-plane (1-102) sapphire, C-plane (0001) sapphire, and M-plane (10-10) sapphire) to achieve different decomposition modes. We have clarified the well-ordered alternating arrangement of Ti- and V-rich epitaxial thin layers. By characterizing the phase structure, thermochromic performance, and durability of the decomposed films, we have found that the derived films exhibit superior optical modulation upon phase transition, significantly reduced transition temperature and hysteresis loop width, and high degradation resistance. Using the new approach, it has become possible to tailor the microstructure of the thin film, and thereby achieve excellent performances. cxun@mail.sic.ac.cn